Brew the tea double strength (2 tea bags for 12 oz of water, or 4 for 16 - 20 oz.)

Make sure to chill it or leave it out to room temp. so the ice doesn't melt when you mix it.

Mix equal parts of the tea and lemonade...If you like yours sweetened only by the lemonade skip to step 4.

Now if you want it sweetened with Simple syrup as well then here is the steps.
One pump =s 1 tbsp or 1/4 of a shot glass.

3 pumps for 12 oz (tall)
4 pumps for 16 oz (grande)
6 pumps for 24oz (iced venti)

(Though I am sure you will experiment with how sweet you like yours.)

Now add a 1/3 ice (This is Starbucks standards though you can add as much or as little as you like.)

Now pour it into a shaker and shake it 10 times...If you don't have a shaker then pour it 10 times in between two glasses and enjoy.

I will see about doing a how to on Simple Syrup for those who don't know how to make it.