Instructions
Load the "Nintendogs: Dalmation and Friends" game.
Press the "L," "R," "a," "b," "x" and "y" keys simultaneously when you see the start-up screen, which features a red Nintendo logo on a white background. If you have done it correctly, a dialogue box will appear, asking if you would like to delete your file.
Use the stylus to select ̶0;Yes.̶1;