Its very simple to shade. All you need is a light brush (like an airbrush with the opaicity of 50%), and a colored drawing! Some ppl can't say they do shading. Well thats what they think, some ppl like me, think you can. Some ppl say shading is hard. If you take the time to read this, you might learn somthing.
Once you've colored ur picture, grab the lightest brush you can find. If you can, put the opacity (how heavy the color is). If the sun is pointing left, you shade right. If its pointing up the shade is dierectly down. If you are shading, do not use a random color if want to shade corectly. You need to use the a darker color of the part of the object. In other words, use a darker shade to shade the object. It would most likely be the BG (background) color, which is below the objecrt, so the objest is standing on. Remember, for best results; use a light brush. Use somthing light, not opaque. If your BG is white, use a very, very, very, light-ish grey. If your BG is black, no need to shade, unless if there is a darker color than black.
I hope that helped you guy's!
~Scourge435 :3