If you get stuck and there's one tile you just can't match, use the Eye of Horus to help you out. Just click on it, then click the tile you want and it will automatically convert!
Bombs and Color Bombs:
Make a match 4 to create a bomb, or a match 5 to create a color bomb.
These bombs must be swapped to make a match, but then blow up all the tiles around them or all tiles of the same color on the board!