I primed the models using a Citadel Chaos Black, and allowed it to dry overnight. I like to shake my spray extensively and keep the can in a warm place, in direct sunlight when possible, prior to spraying as warmer spray goes on cleaner.
I took the cap to a Citadel paint that had dried out long ago, and put in about three parts Codex Grey to one part Bleached Bone. Added some Future Floor Wax, and a few drops of water. This created the base coat gray that I painted one coat of over the hull.
Once this dried, I used Warlock Purple and using an image found while searching on google images (which happens to be the same image seen above) I free-handed the design as close to that image as I could. I took extra special care with the nose of the craft, and then in other areas just made squiggles in the appropriate shapes, trying to leave the appropriate space clear for the "paths" of the design, as seen in the 3D reference.
I thinned down some of the Warlock Purple with water, and gave some of the aft sections a wash, filling in some of those crevices with a purple shadow. Once this dried, I washed the models with Future Floor Wax straight out of the bottle, which not only protects the model, but gives it a shine that I felt was appropriate for our vorlon inspired armor. I'm sure 'Ardcoat from Citadel would work just as well, but I really like Future Floor Wax, both as a paint thinner (it seems to work really well with surface tension on the model) and as a varnish. If you don't want a gloss finish, just spray a Matte Varnish over the Future Floor Wax and it'll tone down the gloss a great deal.
After the Future Floor Wax dried, I painted the gun placements Chaos Black, and then the raised edges were painted Mithril Silver, before getting a Badab Black wash (thinned down Chaos Black works too, if not with a slight gloss). I then highlighted the washed placements with Mithril Silver again.
Finally, I highlighted the hull of the ship behind the main wing section, and a few other places I felt would be appropriate. I began with my base coat color with a bit more Bleached Bone mixed in, and did a final highlight of stright Bleached Bone.
I hope this helped.