USE WITH CAUTION.
You must delete your save first before you can do it. Use the last option in the main menu to delete the save.
While selecting the new game option, hold ++++ (R + Left C + Right C + Z + A), make sure to hold last.
A new screen will appear with a bunch of settings. Use to access TYCONF.SF tab, to access TYCONF.SU tab, and to access TYCONF.SU(28) tab.
You can select an option by using the Control Stick, and press /// to change the option’s value that’s attributed to it.
WARNING: Do not enable TYCONF.SU DEBUG (Option 15) on a flashcart as it may corrupt the SD card, and on an emulator, the game will potentially glitch.