A lot of image work is not design. It is pointing. "Click here." "This is the error." "Ignore that part." That happens when you help a parent with an app, explain homework, file a bug, or send a how-to in a family chat.
A simple Paint workspace is usually enough. You do not need layers and blend modes for a red circle.
Mark it up
- Open Paint and load the screenshot.
- Use an ellipse or rectangle in a bright color to circle the control.
- Cover emails, tokens, and account numbers with a filled rectangle when the data is actually sensitive.
- Add a short text label if words help, then download the PNG.
Why solid cover beats blur for secrets
Blur looks tidy, but short interface text can sometimes be guessed after heavy pixelation. A filled rectangle removes the information. Save blur for faces and background context. Use solid cover for anything you would not read out loud on a bus.
One circle and one short note beat five arrows. If the explanation is long, put it in the message and keep the image focused on where to look.