Once you have the entire box covered, let it sit for a couple of minutes to allow the stain to soak in, then wipe it off with a rag. (diywell.com)
Also, did you brush it on, then wipe it off with a rag as you went along? (beneathmyheart.net)
Having to vacuum the top of my smart speaker instead of just wiping it off with a rag is something I never thought I'd have to consider, yet here we are. (theverge.com)