How to make footer fixed to the bottom in Bootstrap?

By new class in Bootstrap 2.2.1: navbar-fixed-bottom

Bottom description 

How to add Bootstrap into ASP.NET MVC 3?

http://www.codeproject.com/Articles/404633/Transform-ASP-NET-MVC3-Default-Template-with-Twitt

Download different themes from
http://bootswatch.com/

How to upgrade ASP.NET MVC 3 to MVC 4?

By nuget package:
PM> Install-Package UpgradeMvc3ToMvc4

https://nuget.org/packages/UpgradeMvc3ToMvc4