Cover all points of entry. Windows and doors should be closed. Tailpipe should be covered
to a fair the well with multiple layers of plastic. Intakes (depending on the brand/type) should also be covered in the same manner. Also look over your vehicle for any egress points that may need to be covered as well. Get underneath your car with a flashlight and check it out. Any opening larger than a dime is an invitation for critters to nest. Fender liners are famous for holes/ill fitment that allows infestation.
I just got a clear image in my mind of some poor mouse getting shot out of a tail pipe