To signup people to an event:
Choose the Event you want to add someone to
Click the Sign up Button
You will then be taken to a signup screen where you can filter on your members and choose who to signup.
If you want to notify the member of the signup, please check the box "Notify Members"
Click the "Registered" checkbox next the members you want to signup for the event.
Once signed up, you can now see the details in the occurrence details grid:
NOTE: You can notify or reschedule any registered member by just clicking the "Notify" or "Reschedule" buttons on the expanded row.