How to Hold in a Fart Like a PRO
The key is to not allow any space in between the buttcheeks. It helps to visualize what you're doing so try to imagine yourself squeezing an ant's head between your asscheeks. The trick is to keep doing this and hold it until you feel the fart give up, gurgle and fly back up your digestive tract. If you don't wait until this happens then the outside air pressure in your underpants will suck the fart out like opening the door of an airliner at 20,000 feet up in the air.
At the nearest opportunity you should run outside and release the fart because doing this too often could make the gas explode in your heart which usually leads to death. At the very least you will experience a heart attack or as we in the business like to refer to it, a fart attack.