Here is the simple guide on how to install apps on your Apple Watch..
How to Install Apps on Your Apple Watch
1. From the paired iPhone, install or update the app you want to place onto Apple Watch – this is done through the traditional App Store in iOS
2. Open the Apple Watch app, then go to “My Watch”
3. Scroll down in the settings panel until you see the name of the app in question (for example, Sky Guide) and tap on it
4. To install the app onto Apple Watch, flip the toggle next to “Show App on Apple Watch” to the ON position, this will trigger the “Installing…” process
5. Decide whether to show the app on Glances or not by toggling ‘Show in Glances’ to be ON or OFF as desired (ON is often the best)
6. When finished installing, find the app on Apple Watch screen
Now you just need to return to the Home Screen of Apple Watch, tap on the freshly installed apps icon, and you’ll be using the newly installed Apple Watch app. If you enabled the Glances view for the app, you’ll find it when you swipe up from the clock screen as part of the glances.