Clench your fists to attempt to hold it in. Bite your lower lip (if necessary). Do anything to discreetly try and mask that you have to fart. If the feeling increases, clench your buttocks muscles. Hard.
If people start suspecting that you farted, pretend to smell the air about you. Announce “This room smells like farts”. This will transfer the suspicion to someone else. Act like you have no idea who did it. Remember, there are several people around you. It could be any of them.
