There are a few things you can do to prevent mosquito bites when sleeping. One is to sleep under a mosquito net. This will keep the mosquitoes from getting to you while you sleep. Another is to use insect repellent on your skin before going to bed. This will help keep the mosquitoes from biting you. Finally, make sure that there is no standing water near your home where mosquitoes can breed. If you do these things, you should be able to avoid most mosquito bites while sleeping.