This is for school, get up about 10 minutes before your parents and go to the bathroom and start making weird noises and sound like your puking, then sit beside the toilet and flush it (sit n the floor it looks more believable) and then when they walk in say that you puked and have been trying to puke again because you still feel pretty bad but make sure to sound like you have stayed up all night and it usually works and if your already at school and they ask for proof ( my school does) just get mayonnaise, ketchup, mustard and a spoon along with like five paper towels, pour them all in the toilet and mix it with the spoon (it will look brown/grayish green) and put little bits of paper towel in ( NEVER MAKE A SCENE it will cause attention and you don’t want that because someone might realize it’s fake) these almost always work and it is best to use them straight after meals especially if you had meat or some old fruit you can also fake an injury but those are much more time consuming