To compare the cards, surf to medicare.gov (or call 800-MEDICARE), type in your meds and check out the different prices. (Check often, since the site isn’t complete and the discounts don’t begin until June.)

Read the fine print. The cards can change the prices and drugs they cover weekly–and you can swap cards only once.

If your income will be less than $12,569, the card is free and offers up to $1,200 toward the cost of your drugs.

Keep your options open. Often, online or Canadian pharmacies can beat the prices. (Sites like pharmacychecker.com will help you compare options.)