As promised here is my quick tutorial on how I transfer a drawing to the final paper while trying to preserve the spontaneity and spirit of the original.
#1: Here is the original drawing: carmine-red colorase pencil on bond paper.
#2: Photocopy the original drawing at kinkos to make it black/white and scale to the desired size. Tape this photo copy to the back of your nice paper using guides drawn on the back to center it. Use a low-tack tape (such as drafting tape or artist's tape) so that you don't rip the paper when you eventually remove it.
#3: Have a scrap piece of the same high-quality paper you are transferring to off to the side to test what grade of pencil will work best for this particular drawing/substrate. Start the drawing off holding the pencil at an extreme oblique angle to make soft, thick, gentle lines. You don't want to have the pencil in a detail-death-grip as you don't want to commit to any strong lines yet.
#4: The drawing is transferred using a light-box with broad strokes made using the side of the pencil.
#5: Here is the drawing with the light-box turned off to see the strokes better.
#6: A detail shot to show how soft, flowing, and loose the lines should be.
#7: Go back with the point of the pencil to pick out details/ refine your soft lines. The girl on the left has been detailed out, the girl on the right is untouched.
#8: Close-up shot after both have been detailed-out. You do not want to go back over ALL of the lines you established in step 4, the beauty is to pull some out and let others fall back creating subtlety, variation, and levels of information.
#9: Go back like the detail-crazed noodling-freak that you pretend not to be and render the shit out of the hair (or whatever you want to focus on.) Add subtle shadows to the face with a french stub, use a kneaded eraser to pick out highlights, etc. Again, you still want to leave some areas soft and loose.
**To keep the paper from being smudged as you are working keep a paper towel under your hand and pick it up to move it (don't drag it against the paper.)
**Pick a good-quality paper, I prefer Stonehenge and Arches 88 (both are thick, luxurious, and quite smooth for details.) Be a little careful with the Arches though, it is super soft and it's very easy to destroy the integrity of the surface/tooth.
**When taping use artist's or drafting tape.
**To pick the appropriate hardness/softness of pencil, consider the size of the drawing, the tooth of the paper, and the intricacy of the details. Usually the smaller and more detailed/intricate/delicate the drawing and the smoother the paper the harder the pencil you will want to use and visa versa. I usually range from an H to a 2B for the lines and will occasionally stray softer or use powdered graphite for very dark areas when shading, or when I have to cover a lot of area.
Any other questions about this tutorial? Post them as a comment and I'll try to respond as completely as possible!