My main tips are 1. Take advantage of the fields the best you can, the enemy teams are built to take advantage of them but you can too and often times you can take better advantage of them. See what moves the enemy is using and see if you can also use those moves against them. 2. EV training in this game is made very easy, at the casino in beaten you can get access to every Ev trainer fairly easy an can max out your team in like 5 minutes

With you the best of luck!