Are you transfering an image or actually just trying to apply a piece of paper with a drawn image?
When I have done image transfers in the past, I have painted a layer of liquid clay over a clay sheet, then laid the image face down into this, smoothed it over and baked. Once baked, I carefully peel away the paper and the image is transfered. This tends to work best with toner-based photocopies I think, but I have done it with colouring pencil images too.
Another method is to use t-shift transfer paper and print your image onto that, then layer it over the clay and bake.
Emma