You can start earning rewards with your purchase of McCafe items by using the McDonald's App. All you have to do is find the McCafe Rewards punch card located on the home screen and in the Deals section.
Then, just use the mobile order button to select your drink. You can also use the punch card at a McDonald's restaurant or drive-thru.
After you have purchased 5 drinks of any size, you'll get a free drink absolutely free. Go through the steps to redeem your free drink with your mobile order or at your local McDonald's.