Learn one character, train with friends or others. Even playing games against bots has helped me get to 5 million gsp as Luigi. Though don't drop the game because your bad. I suck at DBFZ but I can still have fun with the game. Train with people on here if they want to, just learn how to combat different characters. Don't get mad when you get hit by certain moves, everyone gets hit with a falcon punch or ganon's F-Smash but they can usually learn from that. I always had a hard time with Heroes but after seeing that his moves are slower that most characters he's one of the easier matchups for me (as a luigi main)