Gordon wants to know how to find out how much space he'd need on a thumb drive, can he do it on a drive that has other data on it already, and what is the process for doing this? Leo says that the process of making the recovery disk will wipe all the data from the drive. It will tell him in the beginning of the process how much space he'll need, but typically it's 8GB. The process is very simple in Windows 8. If he hits the Windows key and types "recovery", it will take him to the Control Panel where he can do this. Everybody should have a clean boot disk for their operating system so they can start over if things get messed up.