Should be SKETCHING, not drafting, as sketches are made for ANY type of drawing, drafting, you name it.
It's as easy as it gets, one cardboard box, some extra thick cardboard from another box, a mirror, and a piece of glass, or transparent acrylic.
Cut the cardboard, glue it, and you've made a Drawing Machine, with a 2-way glass, where you see the scene in front of you, and the paper where you draw!
Draw the lines, as drawing on a window, and you are both drawing, and gradually learning to imagine that same glass in front of any scene, one day.
Thanks for the rectification about drafting, rimar2000 :)
Also, Kiteman, here's the actual Illustration, from the 1923 "The boy mechanic" book available on the Net via Project Guttemberg.
Step 1: I Assume You Know How to Draw a Line...
I assume you know how to draw a pair of 45º lines, using a 45º set-square, that you know how to cut Cardboard, and what diagonals are;
Because you have to cut a pair of these shapes, in order to glue them into the inside of the box.