If you already have game ISO/WBFS files, you'll need to do this step.

Install the WAD you downloaded before in the wad folder using the on screen instructions.

Launch the Homebrew Channel again and select YAWMM.

Launch the Homebrew Channel again and select USB Loader GX.

Follow the instructions on this page very carefully to install cIOS.

Make sure you can see USB Loader GX, d2x's cIOS installer, YAWMM, and Nintendont. You can probably install BootMii too, I don't know if it's important.

Follow the instructions on the screen to install the Homebrew Channel.

Wait a moment to be able to skip the scam warning screen.

Browse forwards or backwards a few days until you find the bomb.

On the Wii menu, go to the letter icon in the corner.

Download the other Nintendont files from this folder specifically and put them into the same folder on the SD next to boot.dol.

Save it to /apps/nintendont/boot.dol (must be that exact name). Your SD should now also contain /apps/YAWMM_EN/*. Extract it into the existing apps folder.

Download the USB Loader GX channel forwarder WAD file.

Create a folder named wad in the root of your SD.

Your SD should now also contain /apps/usbloader-gx/*. Your SD should now contain /apps/d2x-cios-installer/*. ( Source.) Extract it to the root of the SD.

Get LetterBomb and choose to bundle the HackMii installer.

Apparently the USB can also be formatted as NTFS. You'll need an SD card and a USB drive, both formatted as FAT32. I'm using LetterBomb, cIOS, USB Loader GX, YAWMM, and Nintendont.

I'll pick one up from a second-hand shop or wait for one online to have a good price. I can't play online with CTGP Revolution because I still don't have a game disc. I'll describe the process I went through in case anyone else wants to do the same. Today I modded the household Wii and put my copies of Mario Kart Double Dash and Mario Kart Wii onto a flash drive to play, since I don't have the discs. Looking for a Mario Kart Wii WBFS download? See here:

Download usb loader for wii