@Ana1234 - People just need to be careful that they use sterilized water when they do that. There have been cases of people dying from infection introduced when they tried to clear out their sinuses and introduced bacteria to the sensitive membranes in there.
I think it should also be said that if you think there is an infection, because your mucus is yellow or green, you're in pain, or you've got a fever, you should go and see a doctor about it.
Doctors tend to give out antibiotics too often these days, but a sinus infection is one of those cases where it's a good idea. They can last a very long time without medication and they get more and more uncomfortable as they develop.
Most cures for nasal congestion are treating the symptoms rather than the actual infection, so don't just rely on those either.