I have both the DJ book and the DJ program/book - the DJ book shows a colour picture of the block with a black and white line drawing of the block beside it. I think they are close to "life" size, i.e. approx 4.5 or 5 inches in size but I am not exactly sure of that. There are usually two blocks or triangles per page, or one triangle (I think). I know some people draft from the diagram/picture only.
I use the program, look at what technique is suggested etc and take it from there, either printing the foundation pieces or templates, or cutting diagram etc. While I am stitching them, I often refer to the DJ book as well.
Hope this helps!
GEMRM