With T3, I would only use in with an AAS cycle. T3 is a strong drug. It will burn through fat! But it will also burn through muscle. You need to be on AAS to help maintain your size. If you are not using gear, stay away from T3 and go with clen instead. Clen will help with fat loss, on the right diet and cardo program.
As for T3 dosing, IF you are on gear, I would start with 25mcg and add 12.5mcg every 2-3 wks, going no higher than 75mcg, and only going that high, IF NEEDED. Then tapper back down at the end.
As for creatine, I would use around 10-15g day, taken preworkout. In general, I would cut it out of the prep at 4 wks out. it can make you hold sub q fluid