All the Styles you need are set up in Word already: many Heading Styles all the way from Heading 1 on down, Normal for your body text, Index Styles, Table of Contents Styles, List Styles; these are all available in the Normal template. If you use these Styles, a Word document will translate into quite reasonably-formatted Braille.
When you use Styles, you have the added benefit that when you want to change the font, size or emphasis of a Heading, you only need to change the Style once – your changes are then applied automatically to every occurrence of that Style in the document.