To allow your friends to follow your bets, you'll need to go into your settings, which can be found by clicking the settings symbol in the upper left corner of the My Action tab. Within settings, click Edit Profile, where you can change your name, add a profile photo, and disable/enable friend following.
You can also return to the main settings page, scroll down, and click Share With Friends to send them your personal link. Alternatively, you can click on the 'share' icon next to the main settings icon on the My Action tab.