Go to the top of your account to the label "Reward Codes". Click on that link. You will be re-directed to the Reward Codes page, where you will enter the Reward Code to redeem it. It doesn’t matter if you enter the Reward Code in all caps or no caps. If you enter the right characters before the code expires you will be credited.
*Any misspellings or typos will result in no credit being applied.*