Geraldrold Maybe do like a recording, on windows they have the problem steps recorder. So if you run it and then click inbox it will take note of the steps you took without you having to take screenshots.
And it's saved as compressed zip file, you upload it to dropbox or something, they download it boom. I mean...its an idea, if you don't think it can be captured by you yourself with screenshot. I know these things happen fast sometimes, it's tricky to catch.