How can one reset a graphic on a button

How can one reset a graphic on a button

Hello,
It is really a beautiful option than, I can display a graphic when a button is pressed. But, I Couldn't figure out, How can I reset the button to normal (previous). Is there a way?
Thanks!
Regards,
Jyo

This is a migrated post! Originally posted on 18.07.2014 by user jyo. Please be aware that information can be outdated.