I get asked about this a lot and was asked to put the answer in a blog.
Get some saline solution for rinsing your sinuses like is used in a Nettie pot or other products. Or just make your own with a little salt dissolved in water. Don't make it too strong... if it tastes like sea water it's probably too strong.
Also get a bowl or pot and an eye dropper to administer the saline solution.
Lie on your back on the bed with your head totally off the bed and bent backwards so that your nostrils are pointing directly at the ceiling. Use the eyedropper to fill each nostril with saline solution. It will feel like your head is going under water and you'll have to breathe through your mouth.
Let it soak into your sinuses for a few minutes or more and then roll over with the bowl under your nose and drain into the bowl. Some of this will also get into the lower sinuses and you'll blow most of it out over the next few minutes.
This process works better than a Nettie pot or other procedures by using gravity to get the fluid into the upper sinuses that cannot be achieved by the others.
Also, to help your body get better, you need to drink 8 to 10, 8oz glasses of water per day that have 1/4 tsp per quart of sea salt dissolved into it. (not iodized salt)
Don't cover up or block your symptoms with drugs/medications. Help your body do the job of flushing out the toxins faster so you can feel well sooner.