Now you do exactly as this page says: you open a command shell, change directory to wherever you unpacked libpandabullet, and run the three commands.
I don’t know what you mean when you say you have installed waf. You don’t need to install waf! The complete build system is contained in one single file: “waf”.
The .bat file is there for just one purpose: because Windows doesn’t support the so called shebang. This is nothing obscene - look it up on wikipedia. The .bat file does nothing but call “python waf ”.
Please not that you have to adjust the path setting withing the file “wscript”. You have to set the path to your Panda3d 1.7.1 installation, to your VS2008 & Windows SDK, and the path to where you have compiled Bullet libs.
Oh, and no grantee that it will compile or run on 64 bit Windows. I don’t have a 64 bit Windows, so I can’t test or fix anything.