There are several strategies that you can use in order to win this game. I use these every time I play, and so far I have NEVER lost. Following these simple rules almost guarantees that you will get that 1st place trophy.
1) This is the most important — NEVER cheat, unless you have to. In the first 2 rounds or so you may not get caught, but in the later rounds, you will get caught most of the time.
2) Put down the cards that you only have one of first. This leaves you with more pairs, triples, and so on, which makes it easier to tell who is cheating.