Confusion about creating a bootable flashdrive I followed the directions to creat a bootable flashdrive for Mac High Sierra. My flashdrive now has the name "Install macOS High Sierra" and it contains the app "Install macOS High Sierra.app". Now comes my confusion. What do I do now. The directions end here. Should I run the app and install it on the same disk? Or should I do nothing. My intent was to make a flashdrive that I could use to boot a Mac computer. If my disk drive crashes i still want to be able to start and run my computer. My flashdrive is 64 GB partitioned into 2 32 GB partitions. I intended to copy a few apps onto the other 32 GB partition. What should I do now?
You may want to delete your answer to your own question. 

In fact:


Insert bootable flash drive 
Open said drive and launch the Install Mac OS High Sierra app
Follow the prompts


You could also reboot the system with the flash drive inserted and holding the Option key. When the drive selector comes up choose your flash drive and installation will commence.

If you run the OS install app from the Applications folder it will install it onto your boot drive. You could do that to install the OS on a thumb drive (just select that drive during OS install) as that makes a good emergency boot drive but it won't make an installer drive.