Farting is one of those things that you'd rather not have in life, but is still unavoidable. Sometimes you feel like farting inside an enclosed space like an elevator or car, and it would really be embarrassing! If you feel like passing gas during an inopportune moment, the best thing to do is try to do it as silently as possible, and as inconspicuous as you can be. The only trouble here is if there are other people in the room who might notice the smell. It's usually worse if there are only two of you, since it's either one or the other. But if there are more people, you can do it discreetly without being discovered.
The important thing to remember here is to reduce the likelihood that you will fart loudly. Try to do it as silently as you can, so you won't get caught red-handed.
Relax. Try to relax your buttocks to prevent gas passing out loudly. Lift off one cheek from the chair a bit by shifting your weight from one side to the other. You can also cross your legs a bit, but this might cause undue stress on your abdomen.
Go slow. Try to hold the gas in. Let it out bit by bit. This might require some effort on your part, but you will need to practice patience.
Try to hold it in. If letting it out slowly is difficult for you to do, then just hold it in. Excuse yourself and head to the bathroom right away.
Some people just can't fart quietly. If you have a difficult time controlling gas, there are several things you can do to let it out more discreetly.
Make a distraction. Talk loudly or play loud music. This is a particularly effective way to distract someone from noticing you've just passed gas. If you're in a vehicle, turn up the radio or open your window. Opening your window serves the dual purpose of letting in road noise and circulating air. This will reduce the likelihood that your fellow occupants will notice you've just farted.
Make noise. As an alternative, if you don't have a source of music or noise, try making other noises. For example, you can cough or clear your throat loudly as you fart. Or, if you're at work, move your chair around such that it squeaks.
If passing gas is inevitable, try moving toward an unoccupied area, or somewhere near a window. This way, there is less likelihood that you will be noticed. If it's not the sound, it will be the smell that will indicate someone just farted. And if there's smell, someone's bound to look for the source. Sometimes, trying to keep your gas in will produce some visible indications, such as struggling on your part or weird facial expressions. Don't be so obvious!
However, if you've just let it out and it becomes obvious that the obnoxious sound and smell came from you, make a sincere apology and excuse yourself. In some cases, humor will help. If you can't be discreet, at least be a sport about it.