No bubblewrap. Just a small applicator bottle picked up at the craft store for about a buck, filled with store-brand mustard. Apply mustard in dots, stripes, whatever, let it dry for a couple of hours, wash it off, and give it a light cleaning with fine steel wool. Repeat until you're happy. I think this had 4-5 applications of mustard on each side. WIP on my ZK here towards the bottom of the page. The ZK was done using a finger to apply the mustard. I like using the applicator bottle better--it gives you more control.