The causes for nasal congestion can range greatly, and you don't have to be sick to be congested. Many people will experience congestion from allergies, temperatures, dust, smoking, spicy food, and air particles.
Recently I was at Contact in the Desert in California and I found myself having clogged sinuses from the blowing sand and dry air. Within two days, I couldn't breathe at all out of one side of my nose and my sinuses got blocked up, causing my face and head to hurt. I needed a solution.
After trying to blow my nose over and over again, I turned to the internet for relief. Sure enough, Google came through.
I found a video by Dr. Adam that quickly and easily explained how to clear sinuses in about one minute using just your fingers — and no, they don't have to go in your nose.