How to deploy (build and run) app on the Apple Watch?

Question

Up until April 24th 2015, development of apps for the Apple Watch has been done using the Apple Watch simulator. Now that the Watch is available, has anyone figured out how to deploy (build and run) apps on the watch itself?

Answer 1

Connect your iPhone to which your Apple Watch is paired. Then you can run the App directly from XCode.

Attaching screenshot for reference

Answer 2

Just build and run your iPhone application. Then, in the "Apple Watch" app on your iPhone, find your application, tap on it, and activate "Show App on Apple Watch". It may take a few seconds until the your Watch app has been installed.