from the picture i would say your spraying metallic silver.
heres some info that might help you:
plastic primer - 1 coat before colour. when painting on plastic
groundcoat or background coat (grey in colour) - usaully sprayed before colour for easier coverage. (optional)
basecoat - mixed 1:1 ratio with reducer. around 3-4 coats or until covered.
tackrag - used to wipe off dust and crap after applying base colour
clearcoat - mixed 2:1 ratio with hardener and around 10 - 15 percent reducer. some come with 4:1 ratio.
apply a semi-wet cover on first coat.
wait for flash off 10-15mins.
apply a full wet cover on second coat.
make sure you have a decent size air compressor for the job cos you'll need constant pressure
or link 2 up if you have small compressors.
and use a gravity feed spraygun a 1.4mm setup.
if its a backyard job you can pick a cheapy for about 50-80 bucks
or get a decent brand gun such as iwata, de vilbiss and sata. from 350-550 bucks if you have the doe