We recommend all users begin to play directly in the web browser and are working towards retiring all installs in the future. To play in browser, they will simply need to log in at https://account.tytoonline.com/login and then press "Play the Game!" from the homepage or sidebar.
If you do need to install directly, here are the instructions:
Download the Launcher for Windows by heading over to https://www.tytoonline.com/install/
Once you’ve downloaded the Launcher, double click to open it. This Launcher manages the downloading and updating of your game.