Most any spray paint will work, some work better than others. Flat and matte spray paint is better than gloss, especially if you are laying down a clear coat. There are translucent spray paints as well which allow for a cool look. Liquitex and Montana are some of the best, big box Krylon and Rustoleum Painters Touch are also good choices. There are lots of methods, typical masking (tape and masking paper or film) and spray for clean lines, or free flow abstract for a more contemporary look or the soap drop techniques to name a few.
Hand drawn pen work: General done with Posca or Boardstixx. There are other brands, specifically geared towards the graffiti crowd. These are waterbased, and were originally used on direct on foam. They work on a finished board, but will rub off and scratch off with or without a clear sealer coat. A clear sealer coat is recommended.
Surface prep is essential. You do not want oils from your hands or old wax or other residues that will get in the way.
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