Often wondered this myself.....have seen other threads dedicated to this....on several forums.
I have not seen a satisfactory answer that would guarantee no damage to suit, AND not peel off after the first dive.
Seems like there should be something you could use....but most paint isn't made to be stretched like neoprene tends to get stretched.....and I think that most oil based products would endanger the lifespan of the material.
I have a light grey suit, Id love to paint stripes on, just so NOTHING would mess with me.:whistling: