If you click on Hand Held contacts you will be directed to the Hand Held Contacts page.  Here you can add or edit users to this add-on. 
To add a user, click the plus sign in the right hand corner. Then you can choose which user from the database you would like to configure.  You will then need to fill in the rest of the required fields. Use the Configuration Note to indicate special setup instructions like custom field inclusion and Synchronization Groups if applicable. Once the user is configured, click the blue save button and the user will be added to the list.  If you wish to delete a user, click the red trashcan. 
NOTE:  Adding a user will submit a Support Ticket to RTG.  That ticket begins a manual process in which an RTG Support Representative must add the submitted information to the appropriate HHC server.  Once the user's setup is complete on the HHC server, a RESEND ALL DATA to HANDHELD command is issued and all HHC data will be synced to the HHC server.  Please be advised that the ticket will be acted upon during normal support hours.  Weekend or after hour submissions may not be completed until the next support session.  An HHC subscription is required.