Written before reading the comments:

1. I take a photo of the door being locked on my phone.

2. I ask my friend if [s]he minds if I add the name of the book to my phone.

3. I put a note on the fridge with instructions.

4. I follow as many of the directions as I remember, then ask another person for directions when I'm closer.

5. I right down the key points and a few specific phrases before the talk onto a single card.

6. I recite the number, using the "obvious" groupings, in this case the 3-digit groupings, repeatedly.

7. The answer I'd predict other people will give is "make a precommitment to only write what you need to get the idea back", but I'm not sure that works.

8. Make virtual flashcards that match faces with bios.