I was playing around with Entity Framework in .Net and when I created a project to use entity framework few library references were missing then I started looking @ if the installation was proper. This is when I discovered how to use the Package Manager in visual studio 2010 to install Entity Framework.
From within your Visual Studio 2010, go to Tools > Library Package Manager > Package Manager Console.
In the console, after the "PM>" prompt, type
you are all set to use entity framework.