ive done several myself... best advice i can give is take your time!
you want to leave at least a whole day between the stages of applying the primer, base coat and laquer. You only want very fine coats too, dont aim to cover the whole section in 1 coat, its best not to! 3 or 4 coats at each stage of spraying is ideal. whole process from start to finish may well take a week.
the secret to success is in the preperation, so make sure you've got various grades of wet n dry paper at the ready to use between layers.
oh and finally, dont spray them and chuck them on your car... after the laquer leave them for 4 or 5 days in the dry to harden properly. Then polish them with a decent polish before putting them on your car!
if you dont do any of the above, they WILL look rubbish