The term 'DRESSMAKER's Guide' refers to a book or manual that provides instructions and advice for dressmakers. A DRESSMAKER is someone who designs, creates, and alters clothing. The crossword solution for this term is 'PATTERN, ' which is an arrangement of shapes, lines, and colors used to create a design. Patterns are often used by dressmakers to create clothing, as they provide a template for the DRESSMAKER to follow when constructing the garment.