There is no formula for ranking. You can't cheat the system. You get noticed by making stuff that people want. If your lwp has a low ranking it means it sucks and you should change it.
Make a detailed or long description for your LWP as long as you can make, it might help in your ranking.
Also include many references to your apps name in the detailed description. Say for instance you developed a: Name of wallpaper: Hello kitty live wallpaper lite, include Hello kitty or whatever your apps name is as much as possible in the description.
