Reproduce the issue once before recording so you know the shortest path to it. Close unrelated tabs, silence notifications, and switch to synthetic or test data if possible. Choose a recording area that excludes passwords, email previews, account details, and other private windows.
Use the screen recorder to capture the steps, the visible error, and a few seconds of context. Stop there. Watch the exported video all the way through before sharing; pause frames can reveal private details that were easy to miss during capture. Check whether the file includes audio you did not intend to record.
A concise clip plus a short written description is easier for support to diagnose.