Um, don't give Smeargle damaging attacks except on the Endeavor set.
Smeargle @ Salac Berry
-Spore
-Substitute
-Belly Drum
-Baton Pass
Spore, Sub on the switch, Drum and Salac, then pass. Enjoy.
Smeargle @ Salac Berry
-Spore
-Endure
-Endeavor
-Extremespeed/Seismic Toss
More novelty, but plenty of fun. Endure an attack from a faster Pokemon for Salac, Spore, Endeavor on the switch, and finish them off.
Smeargle @ Leftovers
-Spore
-Ingrain
-Substitute
-Baton Pass
Only on Baton Pass chains; it prevents your team from being blown away with Roar/Whirlwind and heals the team. The switch-preventing effect doesn't matter since you don't want to switch anyway.
EDIT: Damn, I was beaten again.