I'm very intrigued by the upside down H2O2 (Hydrogen-Peroxid) method. I plan on trying it soon, although I may start with greater than 40 to 1 dilution and see how it goes. I do have a few question I'm hoping you can clear up.
When you say 'point your forehead to the sink' it's unclear if you're talking about having your head flat, at a ninety degree angle to the floor, or further down. I'm a tall guy and my sink is pretty low, so I could have my head almost 'upside down' but even if my forehead is agains the front of the sink, it wouldn' be fully upside down, and it seems the angle is pretty important. If I used the tub I could be fully upside down, but I'm not sure that that is what you're suggesting. Also, I use a waterpik type sinus irrigation device, which puts the fluid in with a little pressure so that it drains out the other nostril. Have you experimented with flooding using larger amounts of liquid to irrigate? There's two positions you can use with this, one is with your head tilted to the side, the other is face down. I imagine with H2O2 (Hydrogen-Peroxid) I'd want to keep my head straight.
In response to the previous post, I found warm dry air is very helpful. In fact, when I get a sinus infection, which I do far too often, despite having had sinus surgery last year, I'll actually take a few days and go to Las Vegas. It seems the dry desert air has a magic effect. As a result, instead of using a humidifier, which also seemed to add mold to my window sills, I use a dehumidifier, although in the middle of winter it might be a bit too dry. I also have my house really warm, and when I drive, the heat on in my car all the time. Finally, I used to use a steamer and a steam room at the gym, but now I go into the sauna. It's really surprisingly effective, and I'll sometimes stay in there for a half hour to really get the effect and drain everything out. I'm getting worried that the anti-biotics that used to work in a few days now only work after a week or two, and that I need oral steroids (pregnasone) to really kick it out. Or a trip to Vegas.