Make combinations with three or more pieces of the same color.
You have to achieve one or more goals to beat each level, so check to see what they are ahead of time and plan your strategy.
There are often different obstacles on the game field that make it harder for you to achieve your goals, so modify your strategy accordingly. You may still need power-ups to overcome some of them though.
Remember, you only have a limited number of moves on each level—use them wisely!
Note that on some levels you have to beat the timer. You get an unlimited number of moves for them, though making your first one starts the clock. You’ll lose if you don’t achieve all your goals before time runs out, so hurry, hurry, hurry!