In case you want forgot to encrypt your home folder while installing Linux Mint or Ubuntu, it’s very easy to do that afterwards, and I’ll KISS, i.e. Keep It Simple & Stupid 🙂

1. login normally at the login screen, let’s say the user you want to encrypt its home folder is called “hobba”
2. Create a new administrative user, let’s call it “olla” for instance
3. Now logout from “hobba” and login as “olla”
4. Make sure the /home partition (if any) has enough free space, as ecryptfs takes a backup copy of all your files
5. Run this command “sudo ecryptfs-migrate-home -u hobba”
6. Preferably just enter the same login password you currently use for the user “hobba”. If not, you’ll have to change your user’s login password again.
7. Wait till the command finishes execution
8. You will see this information displayed, it is VERY IMPORTANT to follow point number 1, you can execute the others if you wish:
   ========================================================================
   Some Important Notes!
   
   1. The file encryption appears to have completed successfully, however,
   test MUST LOGIN IMMEDIATELY, _BEFORE_THE_NEXT_REBOOT_,
   TO COMPLETE THE MIGRATION!!!
   
   2. If test can log in and read and write their files, then the migration is complete,
   and you should remove /home/user.7y3X0vjM.
   Otherwise, restore /home/user.7y3X0vjM back to /home/test.
   
   3. user should also run ‘ecryptfs-unwrap-passphrase’ and record
   their randomly generated mount passphrase as soon as possible.
   
   4. To ensure the integrity of all encrypted data on this system, you
   should also encrypted swap space with ‘ecryptfs-setup-swap’.
   ========================================================================
9. You’re done!
10. Enjoy 🙂

Source: http://bodhizazen.net/Tutorials/Ecryptfs/#Home