Just wondering what you were using to sketch Maya with? Marker~ Can't tell in the picture.
Also wondering if you have advice for drawing on the spot? I did a visit and a kid asked me to draw an animal, and it was like I went blank......ever have anything like that happen? I had feelings of terror, does a camel have one hump or two, are their ears pointy or rounded, what is the shape of their neck, the whole thing freaked me out...I'm not a huge animal person anyway...but eeks!!! It was a sad camel if I do say.
During my recent visit at B&N I used a dark pencil to create the base drawing and then colored with pastels. It's a good way to lay in large swaths of bright color in a short amount of time. Of course, it looks pretty crude until I apply my "magic finger" and blend the colors together. (I get a lot of "Ahhhhs" at that point.) I tried several different media to get that visual punch I wanted - quickly - and pastels seemed to work the best. I do try to keep the kids away from the finished art though as pastels are not the healthiest things in the world. I also recommend people hit the art with a light dusting of an aerosol hairspray to hold the pastels in place after I leave. (I usually sign the art to the venue I'm visiting.)
As far as quick drawing on the spot? Oh yeah, I feel your pain. A friend asked me to draw a quick sketch of my dog Bernie (who hides in all my books) for her daughter. It was so bad, but supposedly her daughter loves it!
You just have to cut yourself some slack on that front. Most people claim not to be able to draw a straight line and they truly appreciate even our roughest efforts.
Note: I'm going to try to be more proactive about answering the questions you leave in my comments - so ask away!