Instructions
Download and extract the HackMii installer that adds the Homebrew Channel to your Wii; that allows you to add new apps to the channel.
Insert your SD card into your computer and access the contents of the card.
Create a new folder on the root of the card and name it "Apps."
Make a new folder for each app you plan to add. For example, if you plan to add a YouTube app, create a folder inside the app folder named "YouTube."
Copy, don't move, app files directly into the new folder.
Locate the app's .elf or .dol executable file, and rename to boot. Leave the existing file extension intact.
Add text and an image to the app's file if there is no icon.png or meta.xml file present. Otherwise, the app will be ugly and potentially difficult to see on the Wii Homebrew menu. To do this, create a folder named "meta.xml" inside the app folder. Open the folder in notepad and add this text: <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<app version="1">
<name></name>
<coder></coder>
<version></version>
<release_date></release_date>
<short_description></short_description>
<long_description></long_description>
</app>
Change "name" to the name of the app.
Place the SD card in your Wii, and you may now load your apps through the Wii Homebrew Channel.