Tip #10: Close shower door after shower, so the mirror won't fog up as much.

I don't know if you already know. I discovered this when I closed the shower door once instead of leaving it open like usually. I guess that this works because it allows the air in the shower cool in the shower and not spread throughout the bathroom.

I suppose you can also do this with a  shower curtain. If you find out, please comment on the post :)