If there are matches available for the ingredient on board to be swapped away from the candy canon, do it as quickly as possible, ideally before another ingredient appears.
Destroy blockers using special candies. Vertical striped candies, and wrapped candies near icings are recommended, as are combinations such as colour bomb/striped and wrapped/striped combinations.
Try to ensure that the second ingredient does not end up on top of a candy canon by switching/not switching column appropriately.
As long as ingredients are appropriately placed (i.e. not directly on top of a candy canon) when towards the bottom of the board, they can be swept off the board by a well-directed special candy or combination. However, it depends on luck.