We cheat and buy Lipton Cold Brew tea bags. Put 2 in a 1 gallon pitcher, add cold water to top. Steep 5 minutes, drink.
We don't use sugar to sweeten, just sweetnlow. 4 packets sweetens the pitcher.
My mom puts tea bags in a small pot on the stove. Covers them in water and lets them simmer a few minutes. Do not boil, will make the tea bitter. She pours the hot tea into the pitcher, adds 1/2 to 3/4 c sugar, stirs to dissolve the sugar, then adds cold water to top.