IT:AD:VST4G:HowTo:Install

Go to http://visualstudiogallery.msdn.microsoft.com/abafc7d6-dcaa-40f4-8a5e-d6724bdb980c

It's a WIP/ so take the time to check/update to the latest version. Since April 2013 (http://blogs.msdn.com/b/bharry/archive/2013/04/26/visual-studio-tools-for-git-update-available.aspx) it's been getting a bit mor stable.