On Jun 8, 11:29*am, mike wrote:
Pencil sometimes works, sometimes not so much. *Maybe it's the wetness
of the lumber; I dunno. *Laying down tape first is too much bother.
Permanent marker is a little too conspicuous, and often a little fat.
I'm considering scoring the wood with a razor to serve as a marker.

Any tips for easily making marks on wet, pressure-treated lumber?

Try chalk or a scraatch awl.
Joe G