Use Color Bursts as much as possible. They will begin to be restored after use as you create matches. However if you are just about to complete a depth level, wait to use the Color Burst early on in the new depth level. Several levels feature rockets that help you earn extra points. They usually appear in strategic locations that give you more points if you do not to move them away. When you find a rocket, consider it it is worth spending extra moves to light it to get a better score.