Technique:
Jal Neti should be done with luke warm water in winter and fresh water in summer. There is a special kind of lota (utensil) with a long  nozzle meant for this kriya. Fill it with water, mixed with a little salt. Sit on the feet. Insert the nozzle into the nostril through which breath flows freely. Now raise the knee on the same side of the nostril and keep the elbow on the knee. Place the lota  on the palm, keeping the other knee parallel to  the earth. Place the elbow of the second arm on the knee as shown in the picture. 

After inserting the tip of the nozzle in the nostril, keep the mouth open, let the water flow out of other nostril. While doing Neti Kriya breathing should be done through the mouth. If mouth is closed water will flow into the breathing canal, which obviously is fraught with danger. Repeat the same kriya through the other nostril also. Remember that not even a drop of water should remain on the walls of the nose. It is important that the inner side of the nose must remain neat and clean. For this, breathe out the water forcibly with the help of Kapal Bhati. Expel every particle of dirt and water from your nose in order to keep it dry.
(SEE KAPAL BHATI PRANAYAM)

Apply Mustard Oil in the nostrils
After the practice of Neti, put a few drops of mustard oil in both the nostrils with the help of dropper. There after draw it inside by drawing the breath forcefully in. This will remove the dryness of the brain. It will also facilitate the practice of sutr neti on the following day. Sutr Neti displaces the mucus. Jal Neti extracts the displaced mucus out of the nostrils. Kapal Bhati dries up the inner walls of the nostrils and applying mustard oil lubricates the  centre of ENT including inner walls of the nose and the throat. Don't you find the above stages of process similar to one used in servicing your vehicle i.e. displacing and removing dust and mud by pressure of water, drying up moisture by air pressure, changing oils for lubricating points and polishing.