This can be checked at any time on the main menu, and if you press a on the card it will tell you what you need to do. As you progress through the game, you will unlock achievements and also unlock cards. Here are a few important notes.
You can not get any cards with two players. So if you got the perfect game on the two controller method, youll have to do it again, against the CPU. Also any wins against MLB teams will need to be redone.
There are two cards for Distance Derby (15 and 20 targets hit), those are not cumulative. In one game, you need to hit 20 targets. What I did, was get to three in a row, let a pitch pass, that way I lose my streak and rinse and repeat. Evenetually it will force you to end the game as long as you keep hitting home runs.