"Use Deodorant before bed for maximum effectiveness."
This one I was a little skeptical of, but the logic checks out. When you go to bed, your body temperature is cooler, so you’re sweating less. This allows the antiperspirant to seep into the pores and clog them. This also signals to the body to stop perspiring, which can make the effects last up to 24 hours, even if you shower the next morning. Despite how clogging the sweat ducts sounds unhealthy, according to health experts consulted it is not.
I’d say put the antiperspirant on the night before, and preferred smelling one (if you have one) on in the morning. And as always, use spray deodorant with restraint, no one loves smelling noxious chemicals in overdose when they get into a crowded area with you.