Four steps, about five minutes. You'll need a Windows PC and your own copy of Mario Kart Wii (PAL / Europe).
Wheel Wizard is the launcher that sets everything up for you.
⬇ Get the latest releaseOn that page, scroll to Assets and click WheelWizardWindows.exe. Open the file once it downloads to install it. (Project home: TeamWheelWizard/WheelWizard)
Open Wheel Wizard, then go to Settings → the Other tab at the top → tick Enable WiiCompiled.
Your Mario Kart Wii file can be any of these formats:
.iso.gcm.gcz.ciso.wbfs.wia.rvzIn Wheel Wizard Settings, find Mario Kart Wii Game File and choose where your file is saved.
Click Play on the Wheel Wizard main menu. Once you're in-game, press F10 to open the settings bar at the top of the screen.