There is no one cure all solution for sinus headaches. Because there are multiple areas where the congestion can be sealing off passages and causing pressure. However, usually it involves clearing the sinus passages through medications with expectorant or anti-biotics should there be an infection involved. Also, in some cases flushing the sinuses with saline (salt water) is perscribed. Check with your doc to really see what's right to do because it can sometimes be hard to tell if it's a plain headache, infection, or something more serious. But here are some things that have worked for me.

Firstly, avoid large changes in altitude, like flying. It may feel okay going up, but boy it isn't comfy coming down, it can even be harmful, trust me it ain't fun.

In any case the best thing to do is take some kind of expectorant like Sudafed to help open up the sinuses and let the pressure out. It's also cheaper to just get the generic brand with the same active ingredients like pseudoephedrine, Phenylephrine, Oxymetazoline, or Xylometazoline

For me sudafed can sometimes make things worse because it drys up stuff up there. So, I take the mucus chest relief stuff with the active ingredient Gauifenesin. It actually loosens the mucus causing the block which allows things to flow better.

Another thing is to try a saline flush which is literally contact lens solution, but you can make your own by just mixing salt into warm water. There are some good instructions here... http://www.entozarks.com/docs/IrrigatingNoseAndSinuses.pdf

You may drink some hot water~~~

Personally I take a Tylenol or whatever other pain reliever I have. Then I take a hot shower and let the water just massage my face. Finally a give my sinuses a nice little rub down.

Sometimes I'll use one of those Neti pots. It first it kind of stings, especially if the sinus problems are pollen related, but then it starts feeling really good after you blow your nose a few times.