Well... first thing you need to do is to export your ship's texture. I usually export it into jpg format, but i dont use gmax/3ds, so i dont know how to do that with your software.
After what I open that thing in photoshop and work on it. If you need any kind of texture (metal, engine, etc) you can either import them from FL vanilla, create them yourself with photoshop or find them on google, quite simple.