How to STOP laughing when you laugh at inappropriate times?

So are you having trouble controlling laugh? Did you ever find yourself accidentally offending someone by laughing?Did you ever feel the urge to laugh at someone who is trying to be serious with you? So what is your tips to stop laughing? I got some, but they are not hellping...simply they are too funny!! :D like: -Open your mouth wide and let the laughter out silently without smiling, this may look odd but it works, -Bite your tounge and pull your cheeks back....or if you are at a funeral or something serious, hold your hands up to your face and smile and laugh as much as you want but try to make the laughing sound like you're crying, -hold your nose and cover your mouth with that hand. Then people can't see your grin, and you can laugh as hard as you wish inside yourself. You may start shaking, but that's OK, it can be covered as crying. Try not to let any sound out, but if you do ease up by accident it sounds much like a sneeze or a strange snort!!!