Things You'll Need
Instructions
Turn on your modified Wii to launch HomeBrew Channel. Select the "IOS Downgrader" option from the Channel's main screen to bring up the "SoftMii Browser" option. Select this option, and press "A" three times to pass through the introductory screens; then scroll down to the menu entry "00000042" ("00000045" for Wiis purchased outside the US) and press "+."
Press "Home" to bring up the "AnyRegion Changer" menu item. Choose this item, and open the "Options" screen. Scroll down to "3.2U" ("3.2E" outside the US), and press "A" to select. Then choose "Yes," then "No," then "Yes" to install only the SoftMii menu additions.
Press "Home" to bring up the "PreLoader" menu item. Select this item, and press "B" to bring up the "Options" screen. Scroll down to "Auto Boot," and select "System" by pressing "Left" on the D-pad, then pressing "A" to confirm and "B" to save your settings.
Choose "Load HomeBrew Channel," select the newly-available "CIOSCorp Installer" menu item and wait for the installer to complete running. This installs SoftMii Gamma and returns you to the Home screen. Then press "Reset."
Select the "SoftMii" menu item, which has now been installed on the HomeBrew channel. Choose the opening and menu screens you wish to use, and press "A" to install the screen. Press "Home" to start using your new screens.