Try to find yourself a good gun cleaning kit (Astro & ATD make a good kit for about $25.00),these kits have all the little brushes and picks you need to get in the little cracks and crevices of your gun.
- Remove the air cap and fluid tip and put the in a separate cup with a good cleanup thinner (PPG's DX 590, or a high grade of lacquer thinner works well).
- Take the needle out of the gun and use a clean cloth with your cleaning solvent and wipe the needle down and put it to the side.
- I like using a small pump up sprayer with cleaning solvent in it to blow through the neck of my gun to loosen up the material in it before I start using my brush to scrub inside the neck.
- Flush the neck out again with cleaning solvent and put gun to the side.
- Use the stiff edge brushes in the kit to clean inside the air cap, paying special attention to the air hole on the outside of the cap. After scrubing the cap with the brush, rinse with cleaning solvent and put to the side. Do the same thing with the fluid tip and put your gun back together.
This is a little more involved than just pouring thinner in your cup and blowing it out, but it will also keep your gun alot cleaner and it only takes about 10 minutes.