[Please excuse the photos from this series--I didn't know exactly what I'd want to cover when I took them, so I am now wishing I had some better shots.]
The first step I took was to make an outline of the main objects by following the grid on my page against the grid over the original image. In the above photo you'll see a reminder of the original picture in the bottom left corner (imagine a grid over it) and part of my first sketch. I marked out where a dark shadow would be over the hand to help guide me later.
Next, I focused on the first hand. (No, I didn't mean to position the kneaded eraser so it looks like the hand is tossing it across the page. :P) Now I'll just talk a bit about drawing as I know it. I don't really know how to organize my thoughts, so bear with me.
So much of drawing (in this style) is not drawing itself, but seeing what needs to be drawn. I have to really study the original that I'm drawing from. If I overlook a particular shadow or highlight, I can throw off the realism I'm after.
To give something a three-dimensional look, it needs to have plenty of shadows and highlights in varying degrees, just like what happens naturally. I try to note spots of dark shading, medium, and highlights, and then plan a range. The darkest shadows can be "black" and the lightest can be "white" (or paper-colored). I need to figure out good mediums for the other areas and be sure they still stand out from the darks and lights. If all of the shadows were just one tone, your picture is then just two "colors" and flat-looking as a result.
Highlights stand out when they are next to a shadow. To bring out contours, it's good to have extremes next to each other. I usually need to exaggerate every darkness and lightness in order to make things stand out as they need to. Note that I put a darker shade behind the fingers so they show up against the background.
Smudging/blending is important, at least in my drawings. Art stores sell stumps and other products to help with smudging, but I find I do the most with either my fingers or Kleenex. I'm classy! I will often start with an overly-dark patch and then smudge to create the medium-range shadows near it.
Erasing is part of drawing. It's just drawing in reverse! I go back and erase-in my highlights since I can't help but smudge too far and darken areas that need to be paper-colored. I erase to bring out bright spots and define edges.
These two images were taken three days apart. When the left photo was taken, I wasn't happy with my work. I almost always get to this point in a drawing where I know something isn't right, but I can't quite figure it out, and I start feeling hopeless like it's too late to fix things. I was having a hard time erasing and blending, so I went to the art store and bought a couple of new supplies. The new pencil I got was soooo helpful in smoothing things out, and the clean eraser helped fix some problem areas.
I also had to go back to the original grid and re-evaluate where I had placed certain shadows and borders. There was some funky roundness on the fingers that didn't look right, so I basically redrew in some of the crucial lines and started over with the shading. It just took some studying to see where I had gone wrong. I don't know if you can even tell (these photos kind of suck) the difference in the two pictures, but some minor changes were done that made a big difference to me.
I had a challenge with my original picture, and that was the blurry patch in the foreground. It's one thing to have blurry cards in a photo, but in a drawing it would just look weird. I decided to just use an actual card as my reference for the card being dealt. I laid down a card and took a photo at an angle that I felt represented the angle in the drawing (and the angle someone would be seeing the card if they were across from the dealer). Then I worked loosely from that photo. It's far from perfect, but I was satisfied (I settle for way less than perfection in my drawings!). I did some vague lines to give the card a recognizable Bicycle look, but didn't stress over the details. I'm just not really a details person when it comes to pictures.
And, as you saw before, this was my resulting picture (after some more shading, erasing, blending, etc. etc.):
Faaarrrrrr from perfect, but good enough for me. I don't know how many hours were devoted to this drawing, but I don't like to push things too far past the Line of Fun, so it couldn't have been that many.
I hope some of my notes were helpful, though I realize I wasn't ultra specific in this entry. Like anything, it just takes practice (something I could use!) and a willingness to try different things to get your desired result. Thanks for reading!
[Some snippets of pictures I've made in the past.]