Painting my bike helmet...what type of paint?

I am a pretty advanced airbrusher and looking to get into painting helmets.

I bought a used bike helmet from the salvation army to practice on. It is really a bicycle helmet, not motorcycle. It didn't have that shiny clear coat you see on professional bike helmets. I bought some Dupli-color Paint Shop Finish System paint from my local auto parts store. I did my usual taping of the design and then hit it with two layers of jet black and 3 layers of clear coat.

It doesn't have that professional shine...is this due to the original paint? should I have used a primer?

Here is the big issue. The paint chips really easily. If you were to rub it the wrong way, it chips!! Also when removing the tape, the edges are not sharp at all and sometimes the paint came up with the paint making the helmet look like...well sh*t.

Is the paint I'm using the problem or the existing surface of the helmet? And why is the paint lifting up with the tape? [I used masking tape rather than blue paint tape]

You sand (abraid) the original surface with 300 grit then prime and sand with 600 grit paper before applying the base coat.

Epoxy for the color
Do your airbrush work with "almost " any paint
Then us a clear epoxy ar urethane for the top coat
"not poly U" like in a spray can -Real stuff

You can use high-gloss or any paint for a helmet. Just make sure you use a primer before you paint. Have fun.

you have to sand the existing paint first in order to 'roughen' it up enough so the new paint will adhere. then primer. after doing this it should not peel.