Below the toolbar buttons near the top of the Phonebook window is the Add New Contact row.  Several options are available here that can speed up adding new contacts.  First, the light grey circle can be clicked orange to mark the contact being added as Selected.  That way, after you hit the (+) button, you can easily find all the newly added contacts using the [ALL] button on the toolbar. You can also use the TAB key (and Shift + TAB keys) to move from one field to the next.  You can provide additional contact info for your teammates by clicking the blue paperclip which brings up a free form box where you can enter things like their company name or other facts important for customer service.  TAB to the (+) button and hit your space bar to save the new contact.

There is one important feature to remember here:  Within the Add New Contact row, there appears a User name.  Mouse over this name and the tool tip will say Assigns Contact to this User.  The User who appears on this drop down button (where ‘Connor Connoly’ appears in the picture above) will be the person to whom any newly added contacts will be assigned.  By default, it will always be you - the person who is logged in.  However, if you work for someone else and are entering contacts on their behalf, you should change this Assigned-to-User so that it lists them as the person to whom the newly entered contacts will be assigned.

Likewise, the User that appears on this drop down button in the Phonebook will also apply when adding contacts from within the Messenger's TO: field.  Pressing the (+) button on the Add New Contact box that pops up in the Messenger's TO: field will assign the new contact to the User that appears here in the middle of your Phonebook.