Word has the tools for booklet folds built-in. Simply configure your mailmerge main document with the required bookfold format and it can produce as many booklets as you need. Since you're apparently doing no more than producing a name/address booklet, a directory merge is needed rather than a table merge. For the directory merge set-up details, see the Merge Labels Using a Down-Then-Across Output topic at: Mailmerge Tips & Tricks (msofficeforums.com)