All of my repo's have a 'build-dev' script in the root of the repository (see here: https://github.com/brightmarch/picto/blob/master/build-dev). Run that after you pull it down and it builds the environment for you (minus setting up Vagrant).

You should commit your asset files in the Bundle, but not the ones in web/bundles/ because those are created by copying or symlinking the assets in your Bundle.