G'Day GloChick,

You do not say what version of Outlook you use....

1. In Outlook Calendar, is there a menu item....
       Edit>Label>Labels ?
   If there is, then you can set the background colour
   of any of your appointments to those shown. In this item
   you may also change the 'text' that describes what each
   colour indicates.

2. Assuming step 1 was ok, create a New Appointment:
       To the right of "Location:", there is a drop-down where
       you may set a Label (text) and thereby set the
       background colour of the _Saved_ Appointment.