Better location for CMake instructions

Building-for-OS-X.md

@@ -17,9 +17,7 @@ cd ~/dolphin-emu
 
 To build with CMake (optionally verbose): Download and install [CMake](http://www.cmake.org/cmake/resources/software.html) if you don't have it.
 
-#### CMake Notes
-
-To build Dolphin from scratch using CMake,
+Then:
 ```bash
 mkdir -p build
 cd build
@@ -27,6 +25,8 @@ cmake ..
 make
 ```
 
+#### CMake Notes
+
 The `-j` option can be passed to `make` in order to compile multiple objects at once.
 A good rule of thumb is number of CPU cores plus one. For example, on a quad core CPU `make -j5` would be a good choice.