I add about one third my grist to the strike water. Stir it in, and bust any dough balls, and repeat. As far as preheating, I never do. I my basement brewery, I used to heat my strike water 2* horgher than what Mashwater told me, and would be spot on each time. Today, my first brew outdorrs in Idaho, on a whim, I went 4* over, and was dead on.