The best strategy is a tight aggressive strategy. "Tight" refers to how many hands you play. Players are categorized as either "loose" or "tight." Loose players play a lot of hands, while tight players are selective about which hands they play. Becoming a tighter player is as simple as folding more hands. You should only play about 15% of the hands you get preflop, and you should probably fold at least 50% of those hands on the flop. (Assuming you're playing in a full ring game.
"Aggressive" refers to how often you raise or bet as compared to just calling or checking. An "aggressive" player is usually betting or raising, which increases her chances of winning a pot when everyone folds. And if a player is both tight AND aggressive, then she has a good chance of winning even if it goes to a showdown. The opposite of an "aggressive" player is a "passive" player. Passive players call bets without raising, or they check and then call when someone else bets.
The best strategy is tight aggressive. The worst strategy is loose passive. Hope that helps.