I love T3, and have used it for either summer prep or contest prep for years.
For a summer prep protocol, start w/ 25mcg for 5 days. Up the dose by .25 mcg every 5 days until you're at 100mcg/day for 5 days. Then reverse and run back down the cycle - this time decreasing the dose every 5 days by 25 mcg.
At then end you'll be happy, assuming your diet and cardio are in order.
By the way - if you're not planning on dieting and doing cardio, then don't waste your time w/ the T3. It's a little added bump to the solid diet and cardio, not a magic pill.