1 old glass juice bottle filled with cold water
1 hot, sunny day
Basically, we just put several (never counted 'em, sorry) teabags in an old glass bottle. We used to use old apple juice gallon bottles when I was younger, but I don't know if anyone makes them out of glass any more. Jam jars might be the only way to go. Anyway, we'd fill up the bottle with water, put the cap on, then park the bottle in the dead center of our driveway until it 'looked like tea.'
The driveway placement is optional...we were just ornery, redneck children.