HOW COULD YOU KNOW?!?!
WHAT IS THIS SORCERY?!?!?
ARE YOU WATCHING ME!?!?
Yes, I am your Big Brother, I am always watching you! I am reminding you that obstructing your telescreen is a criminal offense under the Party law of Airstrip One!
... actually, it's just experience, not sorcery. The quality of your line is consistent with what comes out when you are trying to draw a long line with a writing motion. Add to that the sad fact that most people are taught to write (somewhat) but next to none are taught to draw.
If you have trouble switching to the proper arm motion with a pencil, get some charcoal and practice drawing long lines on a big piece of paper - one a few feet tall. Memorize the motion that you have to make to get a continuous line with those.
Well, to each their own method of learning. The book helped me a lot. Here is my drawing of a DS XL if you want to compare depth and stuff--I need to ruler-straighten the lines, and it's not perfect, but it might help you.
I'm new here. My young-adult sci fi webcomic, Firework, may be found here. It's not very good. Thanks in advance for helping me become a better artist.