How To Use SandCastle To Generate Help Files From Code

1) Generate XML Documentation For SandCastle To consume

To generate an XML documentation file for a Visual C# project

1. With a project selected in Solution Explorer, on the Project menu, click Properties.
2. Click the Build tab.
3. On the Build page, select XML documentation file. By default, the file is created under the specified output path, for example, “bin\Debug\Projectname.XML”.

http://msdn.microsoft.com/en-us/library/x4sa0ak0.aspx

2) Download and install SandCastle – http://sandcastle.codeplex.com/

3) Download and install SandCastle Help File Builder: http://www.codeplex.com/wikipage?ProjectName=SHFB

4) Load up SandCastle and create a new project choosing the .sln for your application. Click Documentation menuitem then Build.

More good info here:  http://grantpalin.com/2010/01/10/net-projects-generating-documentation-with-sandcastle/