Here is a basic description with video.
Here is a description with a more yogic perspective.
Both cover basic techniques and effects. The second goes into some more detail and some advanced work. If you do use the milk for your liquid, please consider the use of raw milk to minimize the inflammatory impact. Please note the second description and its statement that it impacts bronchitis. Generally this technique will only impact the upper respiratory impact, except as the neti works to balance the allergic response, and in this case then, an allergic bronchitis could also settle somewhat.
Interestingly, both discuss the subtle effects of neti. The first tosses it in at the end. But even so it is rather great for a basic how-to description to include it all. The second highlights both the anatomical aspect of esoteric stimulation of the pineal and pituitary gland, as well as a chakra aspect. Neti will stimulate the Moon chakra working then to stimulate psychic abilities and evening out the emotions. Certainly one could explain some of the attributed emotion tonification by the fact that the person's sleep is improved due to an improved airflow in the upper respiratory system after neti. However, many feel jala neti does go beyond that in tonifying the emotions and in development of psychic responses. Try it for a few months and let us know :)