A useful bug report starts small.

Describe the gap

Write down what you expected and what happened instead. Include the exact steps and the smallest input that still produces the problem. A screenshot is useful for a layout issue; an error message and its location are more useful for an exception.

• What action triggers the problem?
• What should happen?
• What actually happens?
• Which browser, language or framework version are you using?

Change one thing

Start from a repeatable example. Read the error location and inspect the values involved before changing the code. Make one focused change, try the original example again, and then check a nearby edge case. This makes it easier to explain why the fix works.

Expected: an empty name shows a friendly greeting.
Actual: the page throws when the profile is missing.
Steps: open the page without a saved profile.
Check next: a name containing only spaces.

Leave a useful handover

A short note should connect the cause, the change and the check. If the bug could return, keep a small regression test for its behaviour. Remove credentials and private customer data before sharing the example with someone else.