(18) Never allow another person to use your computer. Make sure you routinely backup important files to a flashdrive or DVD and store that data offline. Also make sure you have a backup copy of the OS you use as well. If you ever have problems with your OS someday, just wipe your partitioned OS, and then re-partition the OS again yourself from scratch. Do not allow others to 'fix' your computer, they could easily steal information from your OS you might not want them knowing about. Geek Squad works with the FBI and other agencies to steal data from their customers, do not trust them to fix or repair your computer.
(19) Any photos you take with modern cameras contain EXIF metadata that contain GPS coordinates among other data used to identify the owner of the photo. If you store your modern photos online, people will be able to identify you. Don't do it! I repeat: do not post modern photos online unless you want to be identified!
Test your privacy and learn more: https://www.privacytools.io/