Instructions
Load your copy of "Pokemon SoulSilver" into your DS and start the game. Some DS games allow you to reset your data by holding a button configuration as the game is loading, but this is not one of them.
Allow the game to load to the main menu. Press L, R, Select and Start simultaneously to see a message. This warns you that proceeding will delete your game data and start a new file from the beginning of the game.
Confirm that you wish to continue with resetting the old game data. You will lose all Pokemon and any progress that was made in the previous save file. When the process is complete, the game will start from the beginning.