Many of the open text fields have a WYSIWYG formatting menu (Acronym for What you see is what you get). This allows you to choose Bold, Italics, bullet points or insert images.
Follow the instructions to edit your brochure here How to Create & Customise Window Cards/Brochures & DL flyers
Use
your edit pencil and tick the Customise box in the Description.
Highlight the text that you want to adjust and use the Formats button
and choose Headers
You
can click on Headers 1 - 6 to change the font size bigger or smaller.
You also use the Inline and Alignment options to underline or justify
the text.