A notepad?

It's not so much that I'm suggesting you do this, but rather noting that you can.

Have you ever been on the phone or needed to take a note when there was nothing to write on? If a pencil or erase marker (or pen) is handy, and if you have tile counters, backsplashes, or a tile floor - tiles do make a convenient notepad.

You can jot down that info and transcribe it when you can locate somewhere else to write it. Pencil markings can easily be washed from tiles, even some time later. You can jot down that note where you stand and erase it when you no longer need it.

Just a thought.