Flower tiles are pretty common in this game. Try to avoid matching them at the start of the game and uniformly reveal the other tiles around them. Pretty soon you should easily have at least three pairs of flower tiles available to match. Match them consecutively and the achievement is yours.
If you really need it, you could also use the undo and match method recommended by the other guides. Matching the tiles, undoing and re-matching them counts towards this achievement. But you probably won't need to do this with how common the tiles are. However, this is helpful for the following achievement where identical pairs can be difficult to find.