Macworld:

It’s easy to create an external installation drive. It’s also handy to keep around, just in case you’re in a situation where you rather use the drive than rely on booting in Recovery mode.

Here are a couple of different ways you can create a bootable macOS High Sierra installation drive.

I’ll be installing macOS High Sierra on Thursday and after I back everything up and ensuring I have a good bootable backup drive, I’ll do is this. But this line in the article:

…the download will be over 5GB, so it’ll take a few minutes.

Bugs the hell out of me. For many of us, it will take significantly longer than just “a few minutes”. I’ll be looking at over 30+ minutes just for the download.