Hello Dig! I placed mine in the sun to dry and harden. I let them cure overnight (in the garage) and then a couple of days before doing anything with them. I have now covered them all with carpeting.
As for applying with brush or roller, I prefer the brush. You really want to coat the wood well and allow it to soak into the wood, a brush will let you do this better in my opinion.
Hope this helps.
Frey