First Bargue copy

Okay, so I've been figure drawing at this cool classical atelier nearby, and I see the students doing Bargue copies--copies of drawings by Charles Bargue (a 19th century artist who drafted a drawing course that was commonly used in the late 1800s). I decided to give a Bargue drawing a try, and what I ended up with does not look nearly as polished or professional as the ones I've seen at the atelier--but I WILL say that doing this exercise is rapidly improving my eye. I am realizing that I tend to make things bigger than they should be--all.the.time. So even though this looks really pretty not good (ha) compared to some others I've seen, it is helping me to see more accurately, and that's the point right? The question is, how do those atelier students get their dark graphite areas dark without making it look like they every made a stroke on the paper? I don't know. Mine looks a mess, but oh well. Mysteries to be solved in the future, I suppose :)