1. Download KeyMagic form here.
  2. Run the downloaded installer.
  3. After installation is done. Click Log Out to log out and then login back.
  4. Open System Preferences -> Language & Text.
    1. Select Input Sources tab
    2. Find KeyMagic
    3. Check KeyMagic
    4. Then, check Show Input menu in menu bar too
  5. Installation is finished. Select KeyMagic from Input menu and start using it.
  6. You can use Hotkey (⌘+Space OR Control+Space) to switch KeyMagic’s keyboard layouts.