Nasal irrigation with salt water is recommended by 87% of family doctors as an adjunctive treatment to relieve the symptoms of nasal congestion and sinusitis. The simplest method is to hold salt water in your cupped hand, block one nostril while you inhale the water into the other nostril, then blow your nose. The high-tech version is to use a Neti pot, a little jug with a spout. You pour the salt solution from the Neti pot into one nostril and it drains out the other nostril. The technique is described here.
The Neti pot originated in India in Ayurvedic medicine. Neti is Sanskrit for “nasal cleansing.” Other related ancient techniques that have not been adopted by scientific medicine include using a string instead of water and a yoga technique where you close one nostril, pour the solution into the other nostril and allow it to run out of the mouth.