One of the practices suggested in Drawing for the Absolute and Utter Beginner is to take a group of symmetrical objects and to draw them as if they are transparent. The theory here is that when beginners draw overlapping objects they tend to distort the lines in order to make things more visible than they really are. So if you force yourself to draw even the parts which are hidden then this should counteract this effect.
So I grabbed a few tins and other packets out of the larder and roughly arranged them in a layered situation:
Taking my contour drawing practice into consideration I then sketched out the key shapes in pencil - looking for rectangles, ellipses and the like. This proved relatively easy in practice as our brains are very good at filling in missing pieces and coming up with a plausible argument as to how the drawing should look. This, then, is how the piece looked with all lines in place:
Then I decided to fix the visible contours in pen and to remove the pencil guide lines; this should, if the proportions are correct, provide a much more accurate representation of what I was actually seeing. What I ended up with was certainly a clearer drawing of the arrangement but I'm disappointed by many of the shapes; they're intellectually the right shape but their proportions don't match with my perspective view. Still it was an interesting experiment: