Here is an excellent video on how to use it.
I keep two sheets of paper towels, one each to use for blowing my nose after rinsing each side.
Bought the Neti-Pot at Bed Bath & Beyound
This is what the one that I use looks like:
Depending on how much water the one you buy holds, you will use anywhere from one-quarter to one-half teaspoon of salt per fill of the pot. What i do is pre-mix about a couple pints worth, heating in the microwave to ensure the salt is dissolved. Then, as the need arises, I fill the neti pot with the pre-mixed solution and heat in microwave for about 30 to 45 seconds. That is plenty "warm" enough to be comfortable and not burn your nasal passages.
You don't have to buy their special salt. Any non-iodized salt (ice cream freezing salt) will do.