Some tips when sketching in public.
When you are drawing people in public, it’s a good idea to be discreet. You never know how some folks might react. Especially the ladies and vain guys. You know “Metro” guys. Try to be tactful also. Save the mean drawings to do at home. And for the love of god, if you are going to let people flip through your sketchbook make sure there isn’t anything in there you don’t wouldn’t show to your mother!
I recently attended a wedding where this lady fell victim to my pen.