Learn to make an easy, winnable bet with a glass of water by watching this video tutorial. First, take a piece of cloth and set it on a table, preferably one that you have bottom side access to, then take an ordinary cup and fill it with water and set it on top of the piece of cloth. Second, take a hat that would fit over the water-filled glass completely and cover it with the hat. Don't touch the hat in any way after it is placed. Proceed to bend underneath the table so you can pretend your drinking the water from underneath as if there was a hole in the cup and table to let out the water. Drink out loud so it seems real. Next, get back up from under the table and say "there, now do you believe me?" Wait for a moment for someone to pick up the hat to reveal the water-filled glass and then drink it as soon as possible. Say aloud, "I never touched the hat, you did". Now pay up!