The Edge 810/510 have the LiveTrack feature which allows you to share your activity, in real-time, with friends and family through email, Facebook and Twitter.
Before starting, make sure the device software and the Connect Mobile app are up to date. To pair the Edge and your smartphone:
Your device should now say connected and you can start the Live Track:
You should now have a link through the emails or posting to Facebook/Twitter from which people can follow you on the web.
Garmin Connect Mobile app: https://buy.garmin.com/en-US/US/prod125677.html