Set Default Appearance
You can define the appearance of stereotyped elements and connectors as you create or edit the stereotypes, using the Override Appearance and Default Colors panels of the UML Types dialog. However, an easier way is to review your completed profile diagram and set the default appearance of the elements and connectors in place.
Simply click on the required element or connector and press [F4], then define the background, font and border colors and border thickness as appropriate, on the Default Appearance dialog.
When you save the profile containing the stereotyped elements and connectors, make sure that you select the Color and Appearance checkbox on the Save UML Profile dialog.