Choose capacity based on the files you need to carry and how quickly they tend to grow. Photos, video projects, game libraries, and system backups can use space differently, so leave room for future files rather than filling a drive immediately. An external solid-state drive has no spinning disk, making it compact and resistant to some kinds of movement, but it still needs careful handling.
Check the connector and interface supported by both the drive and your computer. A fast drive connected through a slower port will not reach its full potential. Cable quality and length can also matter, especially when transferring large files. Some portable drives include encryption or backup utilities; review how they work and whether you can still access your data if you change computers.
Use the drive for one purpose or organize folders clearly, and eject it safely when the operating system recommends doing so. Portable storage is not a complete backup if it stays beside the computer or contains the only copy of important files. Keep another copy in a separate location and test that files can be restored. Protect the drive from excessive heat, moisture, impact, and unsecured travel.