I tried my hand at Galaxy nails the other day, it took two attempts of layering to get the kind of effect I wanted... but I'm pretty pleased with the results given that I am a novice.
For your own inspiration, and where I got the idea... A Cup Of Jo
I used the nail colours from my recent haul. I started with a dark navy base. Then I had the dark glittery gold, a shimmery silver and just a hint of 'mermaid' green. The idea is once the base is on, to layer like crazy, and to make every nail a bit different...