Let's just say I try to do my best not to look conspicuous lol. Mainly by pretending I'm looking at something else while drawing that person with the combination of my peripheral and memory. If the people look up...I look away.
Sounds like fun, haha. I'd love to start doing this, I've always been a little reluctant because of how people may react.
By the way, how often would you do something like this? As in study strangers and commuters? Do you specifically go out and find people to draw, or do you happen to carry your equipment about with you at most times and just draw when you feel like it?
Aaaaand finally, would it be cool if I asked what you do as a job? Do you draw professionally or more as a hobby/past time?
Well yeah it's a bit nerve racking at first but you start find ways to look less discreet. The trick is to look like you're not looking. Avoid eye contact and you'll be alright...when he looks, look away.
I'm always sketching. I keep a small moleskin in my pocket and a couple pens at all times. You never know when you'll get that Kodak moment so you have to be ready for anything.
Both I'm a freelance illustrator and a hobbyist. At the moment I'm doing cover work for Marvel.