To use gitty as comfily as possible follow these instructions:

save gitty.py wherever you feel like, fx at
/home/user/gitty.py

open a terminal, thats usually done by pressing ctrl + t

cd /home/user
chmod +x /home/user/gitty.py
sudo mv /home/user/gitty.py /usr/local/bin.gitty
gitty create_gitty_db

The last line creates a file in your /home/user/ directory called .two_giraffes.db, hopefully you dont already have such a file
This file simply stores the git repos you add to it, along with a short name for them and their location on your drive

Next version wont have this stupid workaround