in order To Succeed You Must give it 100% Everytime. - Bruce lee.
Put your all into it everytime you jab, work your Jabbing hand really good. use Dumbbells it helps me. i find Bench presses,pushups, single hand high weight dumbell lifts are really effective to me and when you use a heavy bag juss get right into it and try your all in every punch . i hope I'm helping.