Items occasionally got mixed up or balanced out among the three astronauts' kits. Additional items were added by third parties. The job of tracking and packing the PPKs into their bags was by crew equipment engineer Richard W. Nygren. He describes the process in his NASA oral history:
One of the other things we did early on in the program—it got more formalized later on for some different reasons—but the crew was authorized a personal preference kit [PPK]. They get like three-quarters of a pound of personal items that they can take, mementos for themselves or for family and friends. Then there was an OFK, Official Flight Kit, that the agency flew, and we were responsible for packing these kits and verifying that the items got cleaned to the cleanliness specs, and if an item was flammable, that it got blessed.
We’d write the test preparation sheets that gathered all of the kit items and transferred them into bond to get it “legal.” We’d write the TPS, Type A type, to pack it for launch. We worked with the crew guys on all of the pins and medallions and flags and whatever they wanted to fly. A couple of nights before launch, we’re in the crew quarters with all the kit items spread over the beds, going, “Okay, now, this is Dave’s, and this is Jim’s, and this is Rusty’s,” or on the next flight, “This is Pete’s. This is Dick’s,” you know. [Laughs] We would organize it in the bag for each guy, keeping track of each item, because there were a lot of personal items people would fly—wedding rings, items that were important. You needed to make sure that whichever crewman was flying the item knew who he’d actually received it from, so he could get it back to the right people after the mission.
Postflight, we’d get the kits back. We’d take the kits back and clean the items up, because a lot of this stuff was small, and had been wrapped in the world-famous gray tape—it was gray tape back then, and it was like duct tape is today; it solved everything. [Laughs] We’d work with the crews to disposition the items after the flight. Most of the time this was just getting the items to the crew, and they took care of returning them.