Advanced Prompting in Apps

45 min intermediate Lesson 7

Learning Outcomes

  • Configure Custom Instructions and Projects to set a persistent baseline for every chat
  • Elicit step-by-step reasoning with chain-of-thought prompting for harder tasks
  • Steer tone and format precisely using few-shot examples inside a conversation
  • Apply meta-prompting to make the AI write and refine your prompts for you
  • Adapt the same prompt across Claude, ChatGPT, and Gemini for their different quirks

Lesson Plan

Segment Duration Topic
Intro 3 min Why app prompting differs from one-line questions
Demo 1 7 min Custom Instructions and Projects as a persistent baseline
Demo 2 8 min Multi-turn strategy — building, not restarting
Demo 3 7 min Chain-of-thought for reasoning-heavy tasks
Demo 4 7 min Few-shot examples to lock tone and format
Demo 5 7 min Meta-prompting — the AI improves your prompt
Cross-tool 4 min Same prompt, three apps, different behaviour
Wrap-up 2 min Key takeaways, preview file handling

Before You Begin

Pre-work:

  • Working accounts in at least two of Claude, ChatGPT, and Gemini (see Lesson 1 and Lesson 3)
  • Skim Lesson 6: Comparing Tools for a feel of how each app responds
  • Pick one real task you care about — a report to summarise, emails to draft, a decision to think through — and use it throughout

Shopping List:

  • Claude and ChatGPT open side by side (Gemini optional)
  • A short document you're comfortable pasting into a chat
  • A notes file to capture prompts that work — your personal pattern library

1 Set a Persistent Baseline with Custom Instructions and Projects

The biggest upgrade isn't a clever one-off prompt — it's not re-typing the same context every time. Every major app stores standing instructions that apply to every conversation.

Where to find it in each app:

App Where to set it What it's called
ChatGPT Profile (top right), then Settings, then Personalization Custom Instructions
Claude Projects panel in the left sidebar, create a Project, open its settings Project instructions
Gemini Settings, then Saved info Saved info

ChatGPT's Custom Instructions has two boxes: what the AI should know about you, and how it should respond. Fill them like a standing brief:

> About me: I'm a marketing manager at a B2B software company.
> Non-technical. I work mostly in plain English, not jargon.
>
> How to respond: Be concise and direct. Lead with the answer,
> then the reasoning. Use UK spelling. When you recommend
> something, give me the one best option, not five choices.

Claude's Projects go further: you set instructions and attach reference files (a style guide, last quarter's report) that every chat in the Project can see — telling the AI who you are once instead of pasting it into message one of every conversation forever.

NOTE
Why It Matters
Keep these short and durable — stable facts (role, tone, spelling), not today's task. They're silently prepended to everything you ask, so a good baseline lifts every response with zero extra typing per chat. It's the highest-leverage setting in the whole app.

2 Multi-Turn Strategy — Build, Don't Restart

Beginners treat each message as a fresh request. Power users treat a conversation as a workspace, refined over several turns. The AI remembers everything earlier in the same chat, so build on it instead of cramming everything into one giant prompt.

The refine-in-place pattern:

> Draft a 200-word announcement email for our new analytics
> dashboard, aimed at existing customers.

> Good start. Make the opening line punchier and cut the
> third paragraph entirely.

> Now give me two subject-line options: one curiosity-driven,
> one benefit-driven.

You never re-explained the product, audience, or goal — the AI carried that context forward. Each turn is a small, surgical instruction.

Do this Avoid this
"Now make it warmer" Re-pasting the whole brief every message
"Keep that, but change the ending" Switching to an unrelated topic mid-chat
"Give me three variations of paragraph two" Vague "make it better" with no direction

When a conversation drifts or gets cluttered, start a fresh chat rather than fighting the accumulated context. A clean slate often beats a tangled thread.

WARNING
Watch Out
Long conversations eventually fill the context window, and the app starts quietly forgetting the earliest messages. If the AI loses the plot after 30+ turns, summarise the key decisions into one message and start a new chat with that summary pasted at the top.

3 Chain-of-Thought — Make It Show Its Working

For anything involving reasoning, comparison, or multi-step logic, the quality jump comes from asking the AI to think step by step before it answers. A model that rushes to a conclusion makes more mistakes; asked to reason first, it's noticeably more reliable.

The lazy version — and what to do instead:

> Which of these three vendors should we pick?

> Compare these three vendors. First, list the criteria that
> matter for a 12-person team on a tight budget. Score each
> vendor against those criteria one by one with reasoning. Only
> after that, give your recommendation.

The trigger phrases are worth memorising: "think step by step", "reason it through before answering", "show your working", "first... then... finally...". You're not changing the model — only the order in which it does the work.

Use it for comparisons, trade-offs, decisions, maths, logic, multi-step planning, and diagnosing what went wrong. Skip it for quick facts, definitions, and simple rewrites.

TIP
Tip
Some apps offer a dedicated reasoning mode — look for an extended-thinking or deep-reasoning toggle near the message box. For genuinely hard problems, turning that on does automatically what chain-of-thought prompting does manually, and usually better.
NOTE
Why It Works
When the model writes out intermediate steps, each step becomes context the next step builds on — the difference between solving a maths problem in your head versus on paper. Same brain, far fewer errors.

4 Few-Shot Examples — Show, Don't Just Tell

Describing the tone you want works. Showing an example works far better. Few-shot prompting means giving the AI one or two finished examples to copy the pattern exactly. Compare "Write product descriptions in our brand voice" (vague) with this:

> Here are two product descriptions in our house style:
>
> EXAMPLE 1 — The Riverside Tote. Roomy enough for a laptop and
> a lunch, light enough to forget you're carrying it. Waxed
> canvas that only looks better with age.
>
> EXAMPLE 2 — The Field Notebook. Lies flat. Survives rain.
> Holds a year of ideas in 96 stitched pages.
>
> Now write a description for "The Commuter Bottle" in exactly
> this voice and length.

The model infers the rhythm, sentence length, and slightly dry tone — things almost impossible to describe in the abstract. Two examples are usually plenty; three locks it in tight. Few-shot wins for brand or personal voice (tone is felt, not described), structured output (one sample row defines the schema), and classification tasks (examples set the boundary cases).

WARNING
Watch Out
Bad examples are contagious. If your sample has a typo, an awkward phrase, or the wrong format, the AI faithfully reproduces that flaw across everything it generates. Curate examples as carefully as you'd curate the final output.

5 Meta-Prompting — Let the AI Write Your Prompt

The fastest way to a great prompt is often to ask the AI to write it for you. Meta-prompting uses the model to improve, expand, or critique your instructions before you run the real task.

Pattern A — improve your draft prompt:

> I want a prompt that gets a strong summary of a long research
> report. My rough attempt: "Summarise this report." Rewrite it
> to be far more effective, asking clarifying questions first.

Pattern B — make it interview you before doing the work:

> Help me plan a 3-day team offsite. Before you draft anything,
> ask me up to five questions that would most change your
> recommendation. Then wait for my answers.

Pattern C — have it critique its own output:

> Critique that summary as a demanding editor, then tell me what
> to add to my original prompt to get a better result next time.

Pattern B is quietly transformative. Instead of guessing what context the AI needs, you let it pull the context out of you — surfacing requirements you hadn't even articulated.

NOTE
Key Insight
You don't need to be a prompt-engineering expert if you let the model be one for you. Save the prompts it helps you craft and drop the best ones into your Custom Instructions or a Project, so they're always at hand.

6 Same Prompt, Different App — Account for Quirks

A prompt that sings in one app can fall flat in another. The techniques transfer, but each platform leans differently, so you adjust rather than blame the prompt.

Tendency Claude ChatGPT Gemini
Default style Thorough, structured Conversational, brisk Concise, Google-integrated
Long bullet specs Very strong Strong Prefers tighter prompts
Long documents Big pastes handled well Watch length on lower tiers Strong via Workspace
Live / Google info Limited without tools Browsing where enabled Native edge in Workspace

A practical adaptation drill: run one strong prompt in two apps back to back.

> Read the pasted quarterly update below. Think step by step:
> identify the three most important changes, explain why each
> matters for a non-technical exec, then write a five-bullet
> summary an exec can act on. Keep it under 120 words.
> [paste the update]

Run it in Claude, then ChatGPT. You'll often find Claude leans long and structured while ChatGPT leans brisk and punchy. Neither is wrong — but knowing the lean lets you add one steering line ("be more concise" / "expand the reasoning") instead of rewriting from scratch. Keep your best prompts in a notes file with a line on how each app responds; that little table is tuned to your work.

WARNING
Watch Out
Don't assume a prompt is broken because one app underperformed. Before rewriting, try it in a second app. Half the time the prompt is fine and you've simply hit a platform tendency you can fix with a single steering sentence.

Questions & Answers

Q: I set Custom Instructions but the AI keeps ignoring them. Why?
Three common causes. Instructions that are too long or contradictory get diluted — trim to a handful of clear lines. A very long conversation can crowd them out; start a fresh chat. And some apps only apply Custom Instructions to new conversations, so changes won't reach a chat that's already open. Start a new one to be sure.
Q: Isn't chain-of-thought just slower? I want fast answers.
For simple tasks, yes — skip it. Reserve it for decisions, comparisons, maths, and anything where a wrong answer costs you more than a few extra seconds. The trade is speed for reliability, so spend it only where reliability matters.
Q: How many few-shot examples should I give before it's overkill?
Usually one to three. One often suffices for tone; two or three help when you need the model to handle edge cases or a strict format. Beyond about five you're mostly wasting space — and risking that one mediocre example drags the rest down. Quality of examples beats quantity every time.
Q: If I let the AI write my prompts, am I learning or just becoming dependent?
You learn faster, not less. Read what it produces and notice why its version is better — the added context, the explicit format, the constraints. Within weeks you'll write those elements yourself by reflex. It's training wheels that actually teach you to ride.
Q: Should I build one mega-prompt with every technique stacked together?
No. Stacking chain-of-thought, five examples, and a wall of instructions into one message often confuses the model and is hard to debug. Combine deliberately — a baseline in Custom Instructions, one or two examples, and a clear step-by-step request covers most tasks. Add complexity only when a simpler prompt has actually failed.

Key Takeaways

  1. Set the baseline once — Custom Instructions and Projects apply standing context to every chat, so you stop re-typing who you are and how you want answers.
  2. Conversations are workspaces — refine across turns with small surgical edits instead of cramming everything into one prompt.
  3. Ask for the working — chain-of-thought ("think step by step, then answer") sharply improves reasoning, comparison, and decision tasks for a little speed.
  4. Show beats tell — one or two clean few-shot examples lock in tone and format more reliably than any description, but a flawed example poisons the batch.
  5. Outsource the hard part — meta-prompting lets the AI write, critique, and interview you to build better prompts than you'd write cold.
  6. Mind the platform — the techniques transfer, but Claude, ChatGPT, and Gemini each lean differently, so a single steering sentence often beats a rewrite.

Next Steps: Lesson 8: File Handling