This button opens a new window to create a custom template bio.

Load Bio Template dialog/window

As you edit the Font, Font Size, Text Color etc. the preview to the right will update accordingly.  To change a color, click on the displayed color to the right of the color field and the color selection dialog will open.  To select a background image, click on the icon to the right of the Background Image field. 
Note: the last item 'Include Tips and Instructions' is intended for first time users and will include lots of extra instructions in the template bio that will tell you how to get started, but will also need to be deleted by hand.  If you don't want to make all of the extra edits, be sure to uncheck this box.