AMES32 said:
the shading I've never been able to figure out how to do it right.
Going to update this post with a tut for shading, hopefully to help more than just AMES, but even if it only helps him I'll be happy. I'll keep editing this post to keep it in one place, with the current piece I'm working on, so you're going to get a WIP as well
Part one, highlights.

Ok, I personally don't usually do this, but it helps as a visual to decide and place where your light sources are coming from. This will help you place your
shadows (parts of something not in the light. these should get darker the further away from the light source and follow the contour of the whatever shape you're shading),
cast shadows (shadows created by something blocking the light source which can cross into areas that would be lighted if the item wasn't there. these are usually hard lined and consistent in darkness) and
highlights (areas closest to the light source(s). these should give your image that pop, shadows will add the illusion of 3d, highlights will make the image jump out).
This image has 10 light sources, so it might be a bit confusing as to what would and what would not be in shadow, but they vary in direction and height (lower light source from the front, higher in the back).
Shadows - This is where I usually start when doing a picture, as they give the depth.
Highlights - These are where the light bounces off of whatever you're coloring; the closer they are to the light source, the stronger the effect. Since this was done in a comic book style, I'm going to cover that here (if you wanted to do it in a non-comic book style, just remove the inks). In this style you really only have to do highlights for things that are black. When you color your image, you will add the rest of the highlights in there, but you can't get any brighter than white in a B&W image

I've left this undone on purpose so you can see the process. I've taken the areas that are highlighted and removed the black from them. If it was a smooth item, you would be done there, but since this is more textured, I've added that in. I did it by drawing shadows that extend into the highlighted area to convey wrinkles in the leather. Then you have to highlight the part of the wrinkle that goes into the non-highlighted area to finish off the effect. When finished, you should have something that appears black but still establishes detail in your image instead of just obscuring it.
Coloring...
Reflective Light...