thrust him in the opposite direction to the position of his butt. Using this strategy will help you reach as high as possible, just don't forget to collect all the coins while you're up there.
You can use those coins to buy different types of food (which is a key element, remember?). At the beginning of the game, there is only one type of food available, beans; but as you start eating new types of food, you'll discover the different kinds of farts that Tom can create.
Talking Tom Farts is a really hilarious game that includes relatively short rounds (2 minutes max) that'll make you laugh with the different sounds that come out of Tom. It probably goes without saying, but, in order to enjoy the game, it's best if you think farts are funny.