Once the course is entered in the application you will be able to orient yourself simply with the vibrations of the Apple Watch.
Whether you are sailing, swimming or hiking you will be able to follow the right course just with the vibrations of your watch.
The app lets you set a margin of error before the vibrations kick in. When you are too far to the left of a course two vibrations (or one depending on your settings) will be felt on the Apple Watch and vice versa when you are too far to the right.