Does anyone know of techniques to help keep pencil line widths and shades all the same? For example when I use soft leads I seem to have a tricky time keeping lines all the same width and shade. I think the trick is to sort of use the pencil to stroke the paper, but not to apply any direct weight the pencil's tip. I collect animation cels and have noticed that the key sketch belonging to every cel I own has flawless pencil lines that are all the same shade along with being perfectly smooth (meaning they don't look smudgey). Considering that animation is a very well established business, I'm sure there must be a way to figure out how these lines are achieved besides visiting an animation studio and seeing how it's done. Now just to clarify, I'm aware that the final lines are produced by tracing a rough sketch using a lightbox, but I'm interested in exactly how final lines like such are produced by hand.