My piece of advice is that depending on what u answered for the three question they ask u in the beginning of the game, u could see a special scene later on in the game or not and it also determines certain fights and how u level up. So the best way u can fight in the game is if u level up to lvl 7 before u leave the island. It makes fighting a certain person in Traverse Town much easier. Also the order I think u should go in for the worlds is the lvl 1 world, lvl. 3 world, then the lvl 2 world. It will make fighting the boss in the level 2 world easier to fight, since you'll have an easier time fight with.....well you'll find out. But like they said, take your time and have fun!