Although the objective is to collect three Color Bomb candies, you should focus on something else. First defuse the Candy Bombs and then to clear the blockers as quickly as you can. The quicker you clear the blockers the easier it will become to make Color Bomb candies, especially with just five candy colors on the playing field.
Match candies near the bottom of the playing field as often as you can. Doing this will shift the largest amount of candies, hopefully start a chain reaction and create new opportunities to make special candies.
While matching candies at the bottom it can be easy to ignore making special candies at the top of the playing field. So pause after every move and glance at the entire playing field to see whether you can make special candies. It would be a waste to miss out on a chance to make a Color Bomb candy only because you didn’t take your time.