DDRMAX: Dance Dance Revolution 6th Mix Cheats

Move the cursor to the song you want, and when you select it, hold Circle. A menu will pop up and you can choose settings like speed, boost, left, right, mirror, etc.

The groove radar might be confusing but if you hold Start before the song select screen comes up (after you pick what difficulty), there should be numbers on the groove radar. They are pretty small and some are hard to see but it helps a little bit in understanding which songs have more ''groove.'' It's a little bit of timing but once you get it, it shouldn't be hard to get it again.