So you can select up to 5 of the 7 cards ( 4 in your hand, 3 in the tray ). You want to match the ingredients (the number on the card represents its level and does not effect matching at all) in pairs, trios, fours, and sometimes five.
The devil will always pick all three from the tray along wiht the two in its hand.
Rankings:
1 Pair
2 Pair
3 of a Kind
Full house (1 Pair and 3 of a kind)
4 of a kind
5 of a kind
Let me know if you need any further guidance.