Create a C++ Win32 Project. When the wizard comes up, select DLL as application type and check the "Empty project" checkbox.

In order to create functions that'll be available for others to use you need to export the functions, like this:
C++ Code:
  1. "extern "C"{
  2. __declspec(dllexport) void MyMethod(int someParameter){
  3.      // Code.
  4. }
  5. }