If you sweat before, it's better take a shower and then apply. You need to stay with minoxidil at least 4 hours in your head without sweat or wash.
I'm 1 year on minoxidil with good results.. Some regrothw and maintained most of my hair. The results were too slow and i just realize anything after 4,6 months, but it's not the same for everybody. Focus on maintance and keep patient.