# On login screen, press Ctrl + Alt + (F1-F12) to enter terminal mode
# Log in with your normal account in the terminal
# Type this command to temporarily enable the root account and type a password:
sudo passwd root
# Log out of your current account and type "root" to log in as the root
# Type this command to kill any processes using your account to allow editing:
pkill -u <yourLogin>
# Type this command to change the name of the login and the home directory:
usermod -l <newLogin> -d /home/<newDirecotry> -m <oldLogin>
# Once done, you can lock (disable) the root account using this command:
sudo passwd -l root
# It can be done both as the root and your normal account
# You can leave terminal mode using Ctrl + Alt + (F1-F12) (might be different)