The old school way is to place tracing paper on the photo and mark the lines you want to transfer on it. Once you have what your want on the tracing paper place a sheet of carbon or graphite paper on your wood, put the tracing paper on top of it and trace over your lines. This works very well and is easy to do. You can use most computer graphics programs to convert an image to a line drawing and print it out on paper and use this with the carbon or graphite paper. Instructions on converting your image are usually found under print options.
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