What is the best insulation for filling in the seam cracks inside our 10 by 10 Shed?

Question

I would like to mouse proof our shed and we've noticed some mouse tracks. There are also some big spiders with babies. I would like to continue my hobbey in the shed this cold, Draftey winter w/o fear of drafty wind or other unwanted predators, such, as mentioned. P.S. Skunks like to dig under our shed. We've tried everything. Please help us to TAKE BACK OUR SHED!!!

Answer 1

great stuff gap filler. or simply caulk it

Answer 2

expanding foam and wire wool, inside layer  run of expanding foam into all major cracks.  Outside  poke some wire wool into the cracks then fill in with expanding foam.  The wire wool is to stop the mice, rodents wont eat through it. As for your skunks you may just have to kill them on sight, dont give them the chance to spray, a 30 f/lb air rifle should do the job, a .22 slug right to the mid riff