If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
You're working in an alien bar. Aliens will order food. The food will float in the air. Your goal is to circle the required piece of food. When you do it, the piece gets frozen for a while. That's when you need to take it with to the alien plate in the top right corner. The next thing is to select the same color of the plate as the client wants. When it's done, drag the plate with the food on it to the client. When a client has all he wants, he'll show you a yellow circle. When it happens, drag the client to the cashier to charge him.