I read a lot of portfolio case studies. Hundreds every year. And I can tell you with certainty that 80% of them make the same mistakes: they’re too long, too vague, and too focused on the creator rather than the client.

A great case study isn’t a project diary. It’s a sales tool that answers one question: “Can this person solve my problem?” If your case study doesn’t answer that question clearly within two minutes of reading, it’s not doing its job.

The Two-Minute Rule

If someone can’t understand the core story of your case study in two minutes, it’s too long or too poorly structured. That doesn’t mean every case study needs to be short — some complex projects warrant depth. But the key information should be accessible fast.

Here’s a structure that works:

The Hook (20 seconds): One or two sentences that capture the problem and the outcome. “A Brisbane-based fintech startup was losing 40% of trial users during onboarding. I redesigned the flow and cut drop-off to 12%.”

The Context (30 seconds): Brief background on the client, the situation, and why this problem mattered. Keep it to a short paragraph.

The Approach (45 seconds): What you did, in practical terms. Not a blow-by-blow of every meeting and revision, but the strategic approach and key decisions. Two or three paragraphs at most.

The Outcome (20 seconds): Concrete results. Numbers if you have them, qualitative outcomes if you don’t. Include what happened after your work was delivered — did they grow? Did they get funded? Did the solution stick?

The Reflection (15 seconds): Optional but powerful. What would you do differently? What did you learn? This adds authenticity and shows maturity.

Total reading time: about two minutes. Total impact: significant.

The Most Common Mistakes

Writing for yourself instead of your audience. Your case study should be written from the perspective of what the reader cares about, not what you found interesting. A client reading your portfolio doesn’t care about your internal creative process. They care about whether you can solve their specific type of problem.

Burying the outcome. Too many case studies follow strict chronological order: “First I did this, then I did that, then eventually we got results.” Start with the outcome. Hook the reader, then explain how you got there.

Being vague about your role. In team projects, it’s tempting to use “we” throughout. But your portfolio is about you. Be specific: “I led the UX research phase, conducting 12 user interviews and synthesising findings into three personas.” Credit the team where appropriate, but make your contribution clear.

Overloading with jargon. Your case study might be read by someone outside your specialty — a business owner, a hiring manager from another department, a recruiter with limited technical knowledge. Write in plain language and explain technical decisions simply.

No visuals. A case study without visuals is a missed opportunity, especially for design, development, and marketing work. Include screenshots, diagrams, before/after comparisons, or data visualisations. Even a simple chart showing improvement over time makes the outcome tangible.

Client-Focused Language

The shift from creator-focused to client-focused language is subtle but important. Compare these:

Creator-focused: “I wanted to explore a minimalist design approach that showcased my skills in typography and white space.”

Client-focused: “The client’s target audience — time-poor financial advisers — needed information accessible at a glance. A clean, minimalist design with strong typographic hierarchy reduced the time to find key information by 60%.”

Same work. But the second version answers the question every potential client is asking: “What’s in it for me?”

Getting Client Permission

The best case studies include the client’s real name, industry, and a testimonial quote. To get this:

• Ask early. Mention at the start of a project that you’d love to feature the work in your portfolio once it’s complete.
• Make it easy. Draft the case study and send it to the client for approval. Don’t ask them to write anything — just ask them to review.
• Request a quote. “Would you be willing to provide a one or two sentence testimonial about working together?” Most clients are happy to oblige.
• Offer reciprocity. Featuring a client in your portfolio is free exposure for them too. Frame it as mutual benefit.

If a client says no, respect that completely. You can still write the case study with details anonymised: “A mid-tier Australian financial services company” works fine.

How Many Case Studies Do You Need?

Quality matters infinitely more than quantity, but here are some benchmarks:

• Freelancers: 4-6 case studies covering your core service areas
• Job seekers: 3-4 aligned to your target role
• Agencies: 6-10 across key service lines and industries
• Career changers: 2-3 reframed from previous work, plus 1-2 from new-field projects

Each case study should show a different facet of your capability. Avoid repetition — if three of your four case studies are website redesigns for cafes, your portfolio looks one-dimensional.

The Living Case Study

A great case study doesn’t end when the project does. If you can, revisit it six or twelve months later. Add a “Results Update” section: “Six months after launch, the client reported a 25% increase in qualified leads and a 15% improvement in conversion rates.”

This follow-up demonstrates that you care about long-term outcomes, not just project completion. It’s a signal that clients find deeply reassuring.

Write one strong case study this week. Follow the structure above. Get it on your portfolio. Then build from there. One genuinely excellent case study is worth more than ten mediocre ones.