http://www.howtogeek.com/206491/how-to-restore-your-ubuntu-linux-system-to-its-previous-state/

sudo apt-add-repository -y ppa:teejee2008/ppa

sudo apt-get update

If you have installed Aptik, you are ready to install TimeShift and do not need to enter the previous commands. Type the following text at the prompt and press Enter.

sudo apt-get install timeshift