This was done some time ago and was part of a series of cyclamen sketches I did. The flower is cut off on purpose, as I was mostly just playing with shapes. I suppose I was going for an abstract feel to the finished product.
I like playing with toned paper. It's almost more fun for me to be able to create a form by removing colour rather than adding shading. This one's obviously a bit of both, though.
When I'm in the mood to do this kind of thing I usually work in a darkened room with a single light source since it adds emphasis to the shadows. I have a three-bulb adjustable lamp something like this one (but much cheaper) that works really well for that since it allows me to choose how high I want the light to be coming from.
As always, click on the photo for a closer look. Just don't look too closely at the technique...