All jump to step 3 why dont you...
The art of a good finish in good preperation, if the surface your spraying is bad you wont get good results, dont rush, I spray things over several days most people try and do everything within a few hours and botch it.
sand and clean the surface properly
prime the surface then wet sand with a fine paper, even between coats of primer (usually 3-4)
What type of paint is it, solid colour or metalic?
Metalics are much harder to get right, solid colours are way easier, you can cut a flat colour with something like G6 to get rid of the orange peel effect.
Use several thin coats of lacquer, once this is thick enough and totally dry you can also polish it flat with G6.
And yes I am a smart ass, but it wasn't clear from your thread title what you wanted to know... :rasp:
"How to achieve good results using spray paint" might have been been better... and wrong section aso