I just had my 4 wisdom teeth extracted yesterday (June 28th) and I'm wondering how to prevent swelling.?

I heard i should have put an ice pack on my cheeks within 12 hrs after the procedure, i had to drive about 3 and a half hours home right after and was unable to put the ice packs on, but i did as soon as i got home. I woke up this morning and my cheeks were HUGE, and still are. Does anyone know how long it will take for them to finally go down? And how can i help decrease the swelling? My birthday is tomorrow and i don't want to be seen like this :(