Login here: http://www.bookingpad.com/Login
Click on Site Settings > Edit These Details

Change
the Security Setting to 'Members Can View and Book'
Check 'Require New Member Approval'

Members
will be able to Register with the 'Register' button on your booking
site here

When
you login here and Manage Users:

You
will then be able to Filter the pending users and activate them or
remove them:
