For general recommendations on safe computing practices with personal computers and mobile devices, the Information Security Office offers some guidance at https://security.utexas.edu/secure-yourself-quick-guide. This guidance mirrors many of the recommendations and requirements for university work on UT owned computers. Please visit that page for the full guidance, but see below for the main highlights.
Unless you have Windows 10 Home Edition in which case please see https://www.windowscentral.com/how-enable-device-encryption-windows-10-home
Mac Users should use FileVault which is documented at https://support.apple.com/en-us/HT204837
For instructions on how to encrypt your iOS or Android device please see https://security.utexas.edu/secure-yourself-quick-guide#tab-91057
WIPE YOUR DATA - Even if you took every precaution to keep sensitive data off of your hard drive and even if you encrypted it you should always wipe the data from your drive before you sell it, give it away or throw it out.
Here are some general recommendations for how to wipe drives on Windows and Mac computers: https://www.digitaltrends.com/computing/how-to-wipe-a-hard-drive
You should also wipe your mobile devices as well before getting rid of them: https://www.privateinternetaccess.com/blog/how-to-completely-wipe-your-phone-before-selling-it
We remove drives before sending them to surplus and then turn them over to the Information Security Office for secure destruction. If you wish to have your drive completely destroyed you may turn it over to Tech Support (techsupport@mccombs.utexas.edu) to be included in the next batch.