A rapid-tap warning can only occur in Hidden Object scenes. It happens when you tap incorrect items too quickly. An animation will show the glass of the screen breaking. Basically the strategy for this achievement is just to take your time and go slow, only clicking on items you are sure are on the list. You can click on incorrect items, but if you do, wait a second or two before clicking another one. There are a total of 5 Hidden Object scenes. If you have done it correctly, it will unlock at the end of the last one, which is in the temple near the end of the game.