1 piece of card board
2 coffee mug
3 unsuspecting person
Step 1: Observation
Try to figure out when the person leaves his/her desk and comes back this may be helpful in the future.
Step 2: The Fun Part
Then turn it over and place on the table (warning:before perfoming this trick you should practice it a few times) slide the cardboard carefully away leaving a full coffe mug upside down.
Step 3: Results
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