1. Go to the Apple Main Menu
2. Click on "System Preferences"
3. Click on "Keyboard"
4. Choose "Input Sources"
5. Click on the "+" icon
6. Select layout language eg. English
7. On the right side choose layout you want to add eg. Colemak
8. Click "Add"
9. Select layout you just created and close the window.
10. Your layout is up and running... Now you can feel it all around your OS.