Gate passes can be obtained at both the departure and arrival airport. Ticket agents usually are eager to had out gate passes as that means the UM is under the supervision of an adult other than Jetblue and it doesn't take an agent away from their duties as they escort the UM from the counter to the gate and vice-versa.
At the gate the UM is handed off to a gate agent to departure than then escorted down the jetbridge to the aircraft. The UM is then signed for by one of our flight attendants where it is now our responsibility to take care of the UM. When we land the gate agent signs the paperwork and then escorts the UM to the gate or the front lobby, where ever the arrival party is meeting the UM. Full name and address of the person picking up the UM is required upon arrival or we won't release the UM.