Then in the box that appears on the right, click on Redeem a Gift Card. Enter the code NEWSLICK and you should get $1 of Groupon credit. I don’t know how long this credit will be available, so I recommend that you do it now. (It only took me 15 seconds, so stop reading and click!)
P.S. some bloggers are reporting that this credit is only available for new users, but I’ve had my account for some time and it just worked for me.