The method is very much handcrafted, although very simple, and based on a test/error/test mode.
Its effectiveness depends on practice and experience and, unfortunately, is not transferable. You could compare to the use of the sextant, if the sailor knows his profession he may be able to calculate his position to an error of 1000 meters.
The process I usually follow is to draw the approximate profile over a cardboard, then cut it and compare it with the picture or drawing in the same angle. After that a tedious series of pencil marks and cuts follow until shadows, lens distortion and perspective effect are is cancelled.
Next step is to add details and paneling lines to learn about the airplane structure and identify the most probable position of the center of gravity and main wing spar.
Then, practicing a cut at the wing root position, I introduce a rectangle of cardboard that I will cut and try and compare it with the picture, until obtaining a shape most similar to the wing (dihedral angle included).
Same procedure is repeated with the tailplane.
Disassembling the whole thing it is already possible to draw a very basic three view.
It usually is very useful to know the type of engine. If you have this piece of data, you may find out data on the airplane measurements and make an statistic adding up measure on the propellers diameter o air intakes, the size of the pilot head or the height of people and equipment that may appear around the airplane when landed.
Sometimes the diameter of the tyes is a known measure. I have tables with measures of just the Luftwaffe tyres.
Once you have the size, the initial three view is scaled up to the most convenient size and small copies of the pilots and engines, at the same scale, are positioned in the most probable places.
It is not possible to get very much wrong as the inner space always adjusts to these elements.
Same procedure is repeated with small copies of cannons and machine/guns. Some room must be reserved for the most probable position of ammunition containers.
Next step is to imagine the optimum inner structure able to keep all the elements together.
The remaining space is for the electronic equipment, fuel tanks and undercarriage bays.
To me this is a very gratifying hobby that I would like to share with other drafters and modelers. But it is not easy.