You should only inhale steam if your doctor advises it. It's possible to do some damage. Low temperature humidifiers run the risk of promoting infections. So be sure you need such treatment.
Use a neti pot: www.amazon.com/s?ie=UTF8&field-keywords=neti%20pot
The salt is two parts salt and one part baking soda, 1/2 tsp of the mixture in a cup of water. You don't have to use the funny looking pot, but it is more convenient.
Oh i just meant like when you boil a bowl of water and put your face close to it (with a towel over your head); to drip out a runny nose.