How do you moon jump Mario Kart Wii?

You have to get action replay first. Then, put action replay in the slot with Mario Kart DS in action replay. Next, turn the DS on and hit codes. The screen should say that Mario kart DS is inserted. Then hit add new code. Look up the moon jump code. Type in moon jump for the name. Then, type in the correct code and hit save. Lastly, hit boot game with codes. You're done! press B to fly!