#Assuming that you have installed Xcode, Command Line Tools, CMake, and Python
#Install ScipySuperpack
~$ curl https://raw.github.com/fonnesbeck/ScipySuperpack/master/install_superpack.sh > install_superpack.sh
~$ sh install_superpack.sh
#Download OpenCV 2.4.2
#Extract OpenCV-2.4.2.tar.bz2
#Open Terminal at the extracted directory
#At OpenCV-2.4.2 directory:
~$ echo "#define GTEST_USE_OWN_TR1_TUPLE 1" | cat > temp1
~$ cat modules/ts/include/opencv2/ts/ts_gtest.h > temp2
~$ cat temp1 temp2 > modules/ts/include/opencv2/ts/ts_gtest.h
~$ mkdir build
~$ cd build
~$ cmake .. -Wno-dev
~$ make -j8 && sudo make install
#Update your bash_profile:
~$ echo "export PYTHONPATH=/usr/local/lib/python2.7/site-packages/:$PYTHONPATH" >> ~/.bash_profile
#Close and open the Terminal
#Open python console and try to import cv2 to test if everything works
~$ python import cv2