Typical max dose for clen is 150mcg/day
Typical max dose for T3 is 100mcg/day
If it's your first time using these compounds, I suggest you pyramid them up to see how you react.
Clen: Days 1-3 50mcgs, 4-6, 100mcg, 7-9 150mcg, 10-14 150mcg. Stop after 2 weeks, for 2 weeks. Then continue again, however this time you can start at 150mcg, as long as you could tolerate it before. You may want to start at 75mcg or 100mcg, so you don't shock your body with such a high dosage (the sides could be strong for the first few days - bad shakes, heart palpatations, loss of ability to sleep).
T3 - Almost the same thing. T3 is usually run for 6 weeks, however some beleive that there are no ill effects if you run it for even 12 (this is your decision to make, and you should do your own research and come up with your own opinion because there really isn't any hard facts on the dangers of extended T3 cycles).
T3 - Day 1-3 40mcg, 3-5 75mcg, 6-8 100mcg, 9-42 100mcg
Obviously have your diet and cardio in check.
I see no reason to taper them down, most people agree.