Tips and Tricks
Before you attack, study the board carefully and see if you can make any large matches - the bigger the match you can make in the game, the bigger the benefit you'll get to your attacking power or health restoration.
If there are no matches greater than three on the board, see if you can make two different match-threes with just one maneuver. You'll very often have this option when two different clusters of the same color are nearly in an L shape. See if you can slot in the missing piece and clean up on damage.
Keep an eye on your health bar! It's very easy to lose track of your health as you focus on finishing off the threat in front of you. You must survive every single wave of a mission in one sitting, so make sure you're topping up your health with pink match-ups every now and then.
Given the choice between equal match-ups, always look out for the one that will cause a cascade of matches to occur straight afterwards. That way you can enjoy some bonus health or attacking power across the team, without wasting one of your turns!
Sometimes it's worth making a deliberate match failure if it means on the next go you'll be able to complete a mammoth match-up. Just be aware that this is a risky strategy - you'll waste a turn, and you should only do this if you have a lot of spare health across the team.