The cork came pre-finished, but the manufacturer recommended a few coats of water based polyurethane after installation… Today was the day:

I gathered my poly, a paint pan liner, a ‘chip’ brush (disposable paint brush), and an applicator specifically for water based poly which screws onto a standard broom handle. Here’s what I started with:

I started in the furthest corner, working toward the door, in the direction of the tiles, and used the chip brush to cut in the edge. Using water based poly is like mopping with hand soap, or watered down glue- not really in a good way:

After it was done I waited two hours, then it was time to lightly sand the first coat:

After some microfiber-ing, I put on another coat, with probably one more coat to go:

I poly-ed the threshold too while I was at it. Fun tasks for a snowy day!