Agree on price. Pay him, and send him an ink signed copy of yor dealer's FFL.

Your dealer receives it. You pay him transfer fees, background check fees, and taxes if nessicary.

If you have a waiting period, you come back and pick it up when it's over.

I don't know how Kali is on face-to-face or out-of-state buyer/face-to-face transfers. That is all dependant on Kali's and your state's interstate transfer laws.