For Android Wear 1.X watches it may take up to an hour for the watch app to sync after you installed Golf pad on your phone. If it does not, please follow the instructions to Resync Apps as shown in this article:

For Android Wear 2.0 watches, you will need to install the Golf Pad app from Play Store on the watch. Please follow the instructions on this page and search for Golf Pad to get the watch app: