Let's discuss my sketches for "Getting Some Sun", and how the piece evolved over time. I'll comment each image here below:
LINE ART: The first picture in the series is the final line art. You'll notice that much of the line art is actually -very- thin. I tried to make the shading in the drawing do as much of the heavy lifting as possible, so I thinned out everything apart from the character's lines because I wanted him to stand out more against the background. You'll also note that clouds, bushes, and the palm fronds on the tree are entirely missing from the line art.
FIRST SKETCH: This sketch is done as soon as I have an idea in my head. I wanted a character tanning on a chair next to the pool, and I had to let my pen work that out with basic shapes. The key here is to be quick and let my subconscious do the work. It won't be perfect, and it won't have hardly any detail, but if I slow too much in this step, proportions and other crucial big picture stuff goes out the window. You'll note that at this point, I haven't even decided on making a gorilla. That muzzle and ears is my generic furry head I almost always use in early sketches.
SECOND SKETCH: The second time around, I'm still very rough with the pen, but I'm trying to at least get the larger details in - overall shape of musculature, maybe some key features like the tight, revealing underwear and the tank top. This sketch is character focused. I keep the original sketch behind it as a reference. You'll note that at this point, I've thrown out the head and I will be remaking that seperately.
THIRD SKETCH: On the third go-around is when the drawing kind of finds itself. Now it's defined enough that I can focus on finer details. Specific muscle groups or body shape... and a first draft of the head. This is where I decided on a gorilla, and as such, he had to get a little beefier too. The first head is pretty crappy, but I have zero experience drawing gorillas, so at this point, it's just what I have in the back of my head from various cartoons and Disney movies. I've also redone the background here - refining it down a little closer to what I want it to be in the end.
FOURTH SKETCH: Here, I'm redoing the character again, focusing on body shape and trying to iron out the kinks. The changes here are minor - you'll notice for example that his speedos are getting a little thinner and smaller and stretched our and his shirt is riding up a little higher. The arm has also changed (though I'll end up undoing that later)
FIFTH SKETCH: This is a sketch solely for refining the head. I looked at a few references here and gave it a decent shot, but something was missing. The top of the head felt a little too small, and the straight ahead forward gaze always feels a little unnatural.
FINAL SKETCH: I decided the original head just wasn't good enough, and despite working on it for a full evening, I erased it and started over. I looked at more references and I think I got a really decent idea of how gorillas should be drawn. From here, I moved forward into line art - essentially, every layer comprising this sketch was copied (with the originals stored as backup), and then the lines were refined down so they were sleek and crisp. Once all of that was done, I colored the drawing, and then during the shading process, I further tweaked the line art by slimming it down significantly.