rambler420 - Everything that's in this thread is stuff that popped into my head; as long as you don't count a few images for references for the birds. But generally, I have a harder time drawing what someone tells me to draw. But I will say that it gets easier to do with practice. When I first started taking commissions, I had to stop because it was just too hard to put what someone else wanted onto paper. But for me, it was all about broadening what I was able to draw. Every now and then it'll take me a few tries to get someone's commission looking right, but it's just something you've got to learn to get better at.
Normally my best stuff pops into my head, usually at the most random parts of the day, and then I sketch it down later that day so I don't forget it. Then whenever I get the chance, I refine it. But if someone tells me what to draw, it's a different story. I know the same exact feeling as you
moon47usaco - I use ink. Micron and Copic archival pens
Here's that image that had the broken link: