Artist unknown Silas Kopf Martha by Rob Milam Allashka Kosarevskaya Self portrait - Rob Milam Woodworkers Club
Choosing the theme Tracing out full size model and selection of the veneers to use Each section is cut out of the paper model to create a 'window' this allows choosing the orientation of the veneer behind the paper model and then tracing the outline through the window with a scalpel onto the chosen veneer. The matching edges of each adjoining puzzle piece are hand finished using small files and sandpaper glued to shapes of wood for a perfect fit. It's not critical to get the outline perfect, this can be done when the figure is complete. Each piece is glued together with superglue at the edges and taped to the backing paper. Finished model is attached with double sided tape, the outline is scored with a sharp scalpel. A sheet of card has been attached to the top of the model to keep everything in place. Definition of the outline is tedious, repeated strokes are required to gradually deepen the score without a slip. Highlight the score mark with pencil lead.
Deepen the score mark Precise depth routed as close to the score mark as possible. The valley is 1mm deep as close as possible to the oultine mark then final definition with a scalpel again. The scored edge sort of falls into the hole for precise definition The edges of the completed figure are then beveled a bit to enable pressing into the hole for a tight fit. Final result Another example using the same method The text 'Martin' in Japanese engraved about 1mm deep and filled with African Blackwood sawdust mixed with epoxy and sanded/scraped smooth after.
There are quite a few Marquetry techniques, the window method is my favourite and described here. Stock veneer is about 0.6 mm thick, easier to cut but little margin for finishing, one rub too many and you’ve gone right through. I preferred cutting my own about 1mm thick, much harder to nest but a very rewarding pastime.

Examples of some other Marquetry works of art that I have admired.