You get dealt 4 cards after which there's a betting round.
Goal obv is to make a good hand in which you want to make a hand with 4 cards in different suits and of different value (called a Badugi).
You want these cards to be as low as possible.
An ace is low, so the best hand (nuts) is a badugi A234, so all different suits.
Next best hand is A235 different suits and so on.
Actually the highest card counts, so a badugi 2345 is better than badugi A236.
There are 3-drawing rounds (and bettingrounds after each draw) to try to make a better hand and obv, after these drawingrounds the best hand wins the pot.
If noone made a badugi, the best (read lowest) 3-hand wins.
This means 3 non-paired cards of different suits, so if noone has a badugi, A23 in differrent suits is the best hand.
Hope this helps you a bit, but a search on the net will give you much more detailed information.