I wouldn’t go straight clen you need rest. Not only for your body blunting towards but also to rest your heart. You shouldn’t need to go beyond 80mcg
If you only doing it for 3 weeks 2days on 2 days off starting on 40mcg. But if you planning on going longer best would be 2weeks on (mom-fri rest weekends) and 2 weeks off starting on 20mcg
Upping it by 20mcg every 2 weeks