1. Update AppleTV to latest software version through the Settings --> General --> Update Software menu.
2. A USB flash drive 256MB or larger.
Mac - Part 1: Run the installer
Step 1: Download the latest version of aTV Flash from your account.
Step 2: Open the DMG and drag the application to your Applications folder.
Step 3: When running the aTV Flash Installer you will be prompted to select the flash drive you wish to use from the drop down menu.
Step 4: The flash drive will be erased during installation. Be sure to backup any files on the drive you wish to keep!
Step 5: The installer will require an AppleTV update file to complete the installation. If this is your first time installing aTV Flash select ‘Download File’.
Step 6: The installer will automatically download the required AppleTV update file. This will take 3-10 minutes depending on your Internet connection speed.
Step 7: After the download is finished the installer will copy the necessary files to the flash drive.
Step 8: A confirmation message will appear when the installer completes.
Note: After installation a message like the one shown below may appear. This is normal. If the message appears simply click ignore or eject. The flash drive can be removed from the computer and is now ready to upgrade your AppleTV.
Mac - Part 2: AppleTV installation & setup
Step 1: Power off the AppleTV (disconnect power) and insert the flash drive containing the aTV Flash software into the USB port on the back of the AppleTV.
Step 2: Power on the AppleTV (reconnect power) to start the installation.
Step 3: The FireCore logo will appear and installation will begin begin automatically.
Step 4: When prompted, power off the AppleTV and remove the flash drive.
Step 5: Power the AppleTV back on and the AppleTV will startup normally with the added aTV Flash menu items present.