Most portfolio case studies read like a diary: first we did research, then we did wireframes. Readers want the opposite order: what changed, and how you got there.
Lead with the outcome
Open with one sentence on the problem, one on what you shipped, and one on the result. If you have a number, use it. If you don't, describe the change in behaviour you saw.
Show the hard decision
Every project has a moment where two good options competed. Show both, say which you chose and why. That single section shows more judgement than ten process diagrams.
Make images do the talking
- Caption every image with what the reader should notice.
- Show before and after side by side.
- Cut anything that only proves you were busy.
End with what you'd do next
A short honest note on what you'd change shows you keep thinking after the handoff, which is exactly what teams hire for.