Back up any files you want to keep
Insert the thumb drive into your computer
Open File Explorer on Windows or Finder on Mac
Locate the thumb drive
Select all files on the drive
Delete the selected files
Empty the Recycle Bin or Trash
If you want to erase the entire drive, format it
On Windows, right-click the drive and choose Format
On Mac, open Disk Utility and choose Erase
Select the correct file system
Confirm the erase or format action
Safely eject the thumb drive