I am beginning a piece of art, and will use a projector to help layout the general shapes of the image onto the paper. I use a mounting armature that has a clamp as well as a place to attach the projector so that I can position it in any orientation. I am using an Elecwave projector that I bought off ebay for a cheap price. I position the projected image on the page and mark the four corners incase anything moves I can reposition it. I loosely sketch across the details in the image, using my hand to cover the light to check what has or hasn't been drawn yet.