Here's a few recent studies, meant to show the drawing process, but I always find mine tend to have fewer sketch and construction lines evident. I tend to apply them very lightly, and many times just "see" them as I sketch. I always used to think it was because I wasn't really doing the work, but it came from wanting my sketches to look clean. I sort of trained myself to see the foundations and go right to the intended line. I still start with shapes and proportions, but go to details faster than normally recommended. I also have a long running habit of erasing as I go. Once I get line where I want it, I'll "erase and replace" the area to clean up as I go.
Here's a Daffy image. I partly chose it for the small challenge of finishing the drawing, since the top is cut off in the actual scene:

Here's a couple done just sitting on the couch sketching freeze frames. (just picked up the Sat Morning Cartoons 1960s vol. 1 set):
I only partially penciled in details on this pose to show the sketch lines underneath, but the weak blue pencil doesn't show up well in these scans. There's a certain stiffness to these, which comes from an initial copying. Once I learn a character's construction that loosens up.
I wanted to try some Spumco characters as well. I'd heard George Liquor was hard to do. I actually found his construction pretty easy to understand. Only one of these was from a sample (and the middle one didn't really work). They're far from perfect, but for first attempts I think I could get a feel for it:

Jimmy is trickier. Of course, it would have been easier to finish the walking pose if I hadn't placed it too low on the page to begin with. And the one on top definitely went off course:
I wanted to get more study sketching done last night, but my wonderful day job made quick work of that by giving my a cut straight up the tip of my index finger, making holding a pencil like trying to draw with a stinging bee. Thanks, great big drag of a necessary evil-type job! Wasn't enough to just stiffen up my back and limit the amount of time I can sit at a drawing table, I guess.
I started this Bugs last night, but fighting my throbbing fingertip was putting me off. I continued and added more detail to this, the the proportions are badly off (big damn head) so I'm just including the first scan to show some more of the work behind. The red pencil certainly shows better. Is that the purpose of using red, to show the work? I've always known about non-repro blue, but never heard why red was used.

find 'em bigger on flicker: