You can use the instructions from the Mark it Up with Preview guide, linked above, to access the Markup toolbar. We’ll be using Preview’s Markup toolbar, which is usually hidden. In Part Two of the guide, we’ll look at how Preview can be used for viewing and editing images. The Preview app is a handy tool for viewing and working with PDF (Portable Document Format) files, as outlined in the Rocket Yard guide: macOS 101: Mark It Up with Preview.