Be passionate about your teammates. Love the game. Players are not the only people in the game. There are coaches, trainers, announcers, umpires, broadcasters, and writers. All those jobs are honorable professions as well as keeping you young.
Body language screams.
It never whispers. Balance makes champions. If you focus on hitting and ignore the defensive part of your game you will never be a complete player. Be as diligent on defense as you are on offense. Defense wins more games than offense.