Depends on the cause. If it's due to reflux, be sure to manage it with diet, etc. If it's due to allergies, see an allergist to determine your triggers and avoid them. If it's due to impaired drainage after taking a ball, fist or steering wheel in the face, don't try to do the corrective surgery on yourself. See your physician for help in figuring out what to do.
Yes. Try nettipott. To rinse your sinuses. Take steam vapor.