If it's pharm grade start at 20mcg and work your way up every few days when the sides permit. Don't want to overdo it with clen as its long half life is a bitch when you do take a bit much.
Yeah. Re think what the fuck you are doing. What the fuck is this Clenbuterol only shit? Go on a fucking diet. Ketogenic. Toss in some Ephedra at a low dose. Keep it simple.
A lot of pro bodybuilders don't even touch Clenbuterol.