I have adopted a waterproof paper (not rite-in-the-rain brand – can’t recall offhand which it was) and pencil. I experimented with various kitchen papers, bit I’d describe them as “water resistant” rather than water proof. Also I found the contrast between pencil and the parchment was not very good so it was difficult to read, especially in low light.

I also consider white paper as a potential trail marker – to be left on a gate or post etc, so white paper is more distinct than a grey, translucent kitchen paper.

I bought a thick pad of waterproof paper and have added several paged to each (family member's) kit. I didn't see the need to have an entire notepad each, about 5 sheets is enough (IMO).

With a pencil, the paper can even be written on underwater - or in driving rain.