Outlook Form Region - How to Create a Text Box that Allows Text Formatting?

I am not a developer but learning how to create a custom Form Region for a custom Outlook Task form I want to use. I have the Form Region created with a RichText Box but am not sure how to allow the user to format the text they enter, such as bold, underline, and outline formatting. I don't want to force the formatting on the control, but just allow the user to format the text as they see fit. Can this be done, and if so, how? 

Thank you in advance for your help.

Mark