I usually wear an apron when I’m working in my shop. The breast pocket contains a couple of 6″ rulers, a pencil or two, and often a Sharpie marker. There’s a lower pocket in which I usually keep a convertible screwdriver, folding knife, and tape measure. I use stuff from this group almost constantly. The screwdriver especially comes in handy when I’m setting up my tools to loosen and tighten adjusting screws and a knife at hand is always handy.