Is it okay to take percocet (oxycodone) once a day even though it is supposed to be taken every 4-6 hours?

Yes: Percocet can be taken up to every 4-6 hours (although i would not recommend it). However, it should be written as a 'prn' medication, or 'as needed', so you can take it as few times a day as you need to treat your pain. Once your pain has subsided, you can discontinue the medication. Please dispose of them properly as it can be dangerous to leave them around and if someone else takes them.