4: Extract CelesteLauncher.zip into the game's folder
(Where Steam downloaded the game)
5: Run "Celeste Launcher.exe" (Without the "exe" if
your file extensions are hidden) and register/login.
6: In the Celeste Launcher, click the
hammer button and choose "Convert to Steam Game". Click
"Confirm" when prompted. This will make it so when you hit
"Play" within steam for Age of Empires Online, it will
correctly launch the Celeste Launcher.
7: Click the
hammer button again and choose "Game Scan". Set the scan's
location to the game's root folder. Example: "C:\Program Files
(x86)\Steam\steamapps\common\Age of Empires Online" - Once
it's set, run the scan. This will download the rest of the
game files and patch the game.
8: The game is now installed. Press "Play" in the
Celeste Launcher to play the game!