Start at a low dose, say 30 mcgs, and increase by 20 mcgs until you reach the desired level or side get to bad. Clen is a drug that you have to assess your tolerance with so YMMV. I personally am stim resistant and have worked up to 180 mcgs, the safe max dose being 200 mcgs. I have heard of ppl going above 200 but I would not venture into that territory for fear of excess strain on the heart. It is used best with am cardio. If you are looking for a stack, stack it with t3. Taking the two together will create a synergisitc effect greatly increasing results and the amount of time that your body will react to the substance without adapting. Main sides inculude sweating, headaches, and hand tremors.