Transferring onto canvas

Once our sketch was finished we lay it face down and scribbled some charcoal on the back then gently lay it charcoal side down onto our canvas and drew over the lines with a pen thereby transferring the image to the canvas. We then got some dryish paint (oils) on the tip of a brush and produced an outline.
We only used blue and red to fill in the shading and cover all the white canvas. The paint was quite dry.