macOS is available by default on Apple computer. If you run a different operating system, please refer to the other section of the documentation.
To run Home Assistant on macOS you need to install Python first. Download Python 3.5.3 or later from https://www.python.org/downloads/mac-osx/ and follow the instructions of the installer.
Open a terminal and install Home Assistant.
$ pip3 install homeassistant
Check this video for the installation on macOS.