A good way to up your skills in MCSG is to train. It could be on a different server, or you could start up your own server and practice with friends.
It doesn't have to even be on MC. I have very lighting quick reflexes, so I dominate in close PvP. I practice on an old game I used to play called AoS (or Ace of Spades Classic (you know, the one before Fagex bought it?)). I just have one stationary bot loaded with random spawns, and I on a flat map, and try to get large combos over and over again. I'd be happy to put one of my best videos up, but I'll need your permission so I'm not accused of adrvertising non-MCGamer content.