Proper paperwork is 2 ATF Form 4s (I believe). Seller (Gemtech) will fill out the first part listing the item, You will out the next section which includes attaching passport type photos and take it to your CLEO. CLEO fills out next section affirming to you lawfullness.
These are then sent into ATF along with two sets of fingerprints and a money order for the black.... Tax.
ATF will then either issue a stamp or denie the application and send it back to you. You then, if approved, sent it to Seller who then sends you it back along with the item.
Simple, isn't it?