Have you looked at my shading tutorial, it might help
. You've got to get pencil to paper and SHADE more, the picture should STAND out of the paper from all the shading you should do. Just take your time, and your drawings will benefit. Hey, its only your second though, so your doing very well. You'll improve, no doubt about it.
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My first car drawing, wish I could still draw this well
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To draw with a broken pencil is pointless.
Call me Ross.