There really wasn't much to it at all. As you can see in the pics above, I got myself a can of Gray and sprayed it for the base. Then I just bought a $1 bottle of Black acrylic from AC Moore (any craft store will have it). I originally tried thinning the black paint with water to do a wash but it didn't seem to work for me.
What I ended up doing was using a foam brush and literally brushing the black straight out of the bottle. I would let the black sit for a couple minutes and then wipe it with a rag to remove the top stuff and hopefully leave black in the grooves. Really it was all trial and error. In the end I used that foam brush to brush the black around the whole ship as it was drying. There was no science to it at all. If an area started to dry and I didn't like it, a couple drops of water brushed on was enough to reactivate the paint and try again.
Honestly, its just acrylic paint. The worst case scenario is that you don't like it and try again. Based on that pic you posted it looks like you have a bit of melting going on there. I am going to guess that no matter what you do it will be an improvement to it. Good luck.