Word's Book Fold setting arranges pages for a folded booklet. Microsoft's guide opens Custom Margins and selects Book fold under Multiple pages, which changes the orientation to landscape. The gutter reserves space for the inside fold and binding.

Set Up Word's Book Fold Layout Before Writing

Choose the paper size and, for longer work, the sheets per booklet before completing the content. Preparing the layout early reduces later cleanup when tables or images must fit the booklet's smaller finished page dimensions.