It's one of the toughest things you have to do mechanically tbh, and there aren't really any shortcuts for it. Also it's easier for some characters more than others. I'd set the dummy to random block and just practice the confirm into cl.C. It helps me to think of it in blocks: you have the cr.B cr.A hit confirm (for many characters, anyway), st.B max mode activation cl.C, then everything else. If you can grind the first two blocks to semi-consistency, the rest can be adapted into whatever you want out of the combo.
and yeah, when you are grinding don't forget to take frequent breaks to let it set it. Overloading will kill your wrists and make you forget things