A simple guide on how to safely install POP!_OS on an external SSD via USB. This method uses the "disconnect all drives" approach, which secures the OS' bootloader so that it is not overwritten by your Windows installation - if you have one. However, if your main operating system is a Linux one, after you reconnect all the hard drives, you can go to your main OS and update GRUB. If the application OS-Prober is installed, the external POP!_OS will be recognized and placed within your main GRUB bootloader. However, you will still have the external bootloader intact for a rainy day!

This is a simple process on how to partition and format a drive for use with Ubuntu Linux.