Question about being a slasher in basketball?

How can i become more slasher-oriented like Dwyane Wade or LeBron James. I see that they can get to the hoop very well and very fast and finish. I'm rather flat footed and not very explosive in my footwork speed which is why i have difficulty blowing by defenders, crossing people over etc. This flaw in my game is really what keeps me from being a solid player. I can never really shake anyone off despite the fact that im 6'2'' and pretty skinny...also on defense when people go up for shots i have a awful hard time reacting in time to their maneuvers to be effective...its almost like my reaction time is slow. How can i fix this. I want to be an explosive slasher who can get to the hole at will and play lockdown D.