How do you use navigate and activity at same time. ie i want to set a course and use the bike activity

Press start, select bike as the activity / app.

From within the bike all hold the menu button (middle left) to bring up the menu

Scroll down to select navigation, then courses, select your course and “Do Course”

Thank you so much for your answer and it works. I find the course is difficult to follow from the watch whilst cycling. I know you can access the course on the iphone but it does let follow the course it is only a map? any ideas? thank you Simon 

It is indeed tough to use a wrist based device (even on handlebars with appropriate mount) while cycling).  Possible solutions, although most are fairly obvious and you have probably considered them already

1. Buy a cycling GPS - i.e. Garmin 520+, 530, 830, 1030.  This is my personal preference.  If provides such a better experience while cycling than a watch or phone ever did for my uses.
2. If your phone is acceptable, use a different app on your phone for navigation.  I think some options may be (most if not all probably require a subscription or purchase):
   1. Strava
   2. MapMyRide
   3. RideWithGPS

Sorry to not have a better suggestion for you.

Thank you so much. I will look at a GPS. The Apple and Google maps are not good as they keeping changing the route. Simon