I have found that a bunch of very thin coats is the best way to get what your looking for. I'm no professional painter, but i do a lot of graffiti and painting car parts.
In a wind proof environment, spritz a very light coat of paint on whatever your painting, let it dry a little, but not completely. Like 3 to 5 minutes, then repeat the spritz and dry method until it's got one good layer of paint. Let it dry completely before you lay on any extra layers. Extra layers should be done the same way the first layer. 2 or 3 full layers should do it, but that's your call. It's a long process, but the results are worth it, to me. It pretty much eliminates runs in the paint.