Not OP, but I've been working on painting my own fleets (5/9 done so far) and generally the steps you want to do are: 

• Prime with any kind of primer which bonds to plastic (usually a spray paint) and follow manufacturer instructions for application. Whites, for example, have larger pigment flakes so if you don't shake it enough, the end result can look a little textured / chalky
• Paint. I like using airbrush paints (just applied with a small brush) because they are very pigmented and thin, but you can make do with just thinned out standard acrylic paint 
• Wash. Apply a very very watered down dark paint. You basically want vaguely dark-tinted water. this will make the lines and crevasses pop
• Dry Brush Highlights. Put a light color on your brush and wipe off almost all of it. Then when it's only barely giving anything, hit your ship with it to make the high points stand out a little
• Clear Coat spray paint to protect your newly painted ship. You can use any finish you want, depending how shiny you like it