My wisdom tooth on bottom right is swelling up right side of my mouth. How do I stop it hurting?

See a dentist. Get treatment. You can mask the pain but the problem is there and needs to be addressed. To help use pain control brush the area, and rinse with warm salt water. You need to keep it clean. But most importantly get the tooth treated/removed.
Pain control. Unless you are allergic, any NSAID like motrin, ibuprofen, naproxen, should control your pain until you can see your dentist for definitive care. A soft diet is helpful.