Creating Mii’s takes a little time to master. Your first few creations might be something you’d like to hide from the eyes of others. You can delete Mii Characters by following this Tech-Recipe.
1. Go to the Wii Main Menu and select the Mii Channel.
2. Select Start.
3. Locate the desired Mii character and grab it by pointing to it and pressing and holding A and B at the same time. Keep holding A and B as you drag the Mii character to the Erase Mii icon on the left side of the screen.
4. As you still hold A and B, you will see the Mii’s face appear in the Erase Mii icon.
5. Release A and B to erase the selected Mii.