Start a local match and then make these changes to the game's settings:
After making these changes, use the D-pad or control stick to navigate over to the player list. Press A on six of your seven bots and set them all to be on a team that isn't yours. Now highlight the last bot, put it on the same team as you, and set its difficulty to Dreamcrusher.
Now start the game, sit back, and the let the chaos ensue. Whether you win or lose, you should level up once after every game. As I said before, the only interaction you need to have with the game at this point is hit the X button after each round to start the next one. Have fun and enjoy effortlessly gaining your experience!
If you've inputted all these settings as instructed, your match should go something like this: