I was cleaning out some of my junk drawers and I ran across an indelible pencil. I wondered out loud to myself if it is still a staple of a prosthetic or orthotic casting kit. I switched to adhesive dots a few years back. I can put the dots directly on the skin (malleoli, navicular, and base of the fifth metatarsal) and the dots are then translated to the mold. It should also be noted that they will show up if you use a scanning device such as the Biosculptor.
Before I apply the dots I always ask if the patient is allergic to any adhesives and I use my best judgement if the skin looks fragile. The benefits of the dots are that they do not move during the casting process like markings on stockinette. The other benefit is my hands are not stained blue along with a patients leg. Here is a picture of the dots placed on a pediatric patient I was getting ready to cast for an AFO.