A very messy medium and one that takes some getting used to. The thing about charcoal is it smudges a lot so you'll have the learn to control your movements without the support of the side of your hand touching the paper. A tip is to use a sheet of A4 as a rest. Another tip is to use compressed charcoal. It has all the advantages of charcoal without the tell tale shatters and splinters that you get from the run of the mill stuff. I would though suggest before hopping right into the world of charcoal that you try starting with wash pencils first.
Wash pencils are like a hybrid between standard graphite and charcoal. They spread a bit better than standard pencils but without the mess of charcoals. They are also water soluble so you get a lot of bang for your buck. The only down side of these pencils is the fact that the darker you go the more shine you get off the finished product. A tip is the apply the pencil dry so you can get an actuate finish then use a small smudge stick or cotton bud slightly moist to take the gleam off it. Another tip is this. If you have a very large area to cover in total black don't bother using a pencil in the conventional way. Get a dark wash pencil and leaning hard fill in the area as best you can. Lots of white bits left exposed is okay. Next get some cotton wool and wet it. Use this to spread the wash around. I'd suggest starting at the bottom and work up. This way any extra water will run off the bottom without damaging the drawing. Do this until you know the right amount of water to use.
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