Image>Adjuestment>Threshold in Photoshop. You could run it through streamline afterwards. I typically trace the image/elements out using the pen tool in Illustrator. It's pretty time intensive but the results are much better this way.
There is no one way to do this. one techniques that I use is put the photo in photoshop and use "filter > sketch > halftone pattern". Then copy the image into illustrator, and use "filter > Pen and Ink > Photo Crosshatch" This will create a line drawing most of the time that looks good.
If you only have Photyoshop and not Illustrator, you can do a manual vector trace there as well using the pen tool. I got the hang of it fairly quickly; there's some decent tutorial you can google up if you need to as well. (Look up using pen tool or similar)
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