How do I include Boost libraries?

First you should read about the difference between #include "filepath" and #include <filepath> here.

Personally, I'm working with Boost from Visual Studio as follows:

1. Go to Project properties → C/C++ → General → Additional Include Directories, and add a path to the boost library root (in my case C:\Program Files (x86)\Boost_1_53).
2. Include a .hpp file in your sources, like #include <boost/lexical_cast/lexical_cast_old.hpp>

If you're using non headers-only libraries you should also add path to Boost libraries in Project properties → Linker → General → Additional Libraries Directories.