If on 4.X or 6.X, installing MSET would be fastest (assuming you have a DS Flashcart)
If on 5.X, 7.X, 8.X, or the above without a DS Flashcart, then Up/Downgrading EmuNand to 9.2, Cloning it to SysNand, then formatting SysNand would be optimal, as then you could start using Menuhax with a Lesshax payload to boot into EmuNand
Although Arm9LoaderHax is the very very best, like nothing ever was