In this package you have everithing, you have to install conky before, according to your distribution
1. files are hidden, if you are using gnome press ctrl + H, with kde ctrl + .
2. copy o cut this files and paste into your home directory.
3. Run conky, press alt + f2 typing "conky" or open the terminal and type "conky"
In the folder .Conky the file gmail.py open it with right click then choose display, you have to change the username for you count gmail and your password and save it.