I will speak of this glitch as if it were held in the item shop at level 1-3.
First, find the shop point stand(You check it to see what you get for shop points). Stand to the right of it, and walk leftwards.
Then, you flip. While in 3D, Hold Left. You should appear above the stand. Now Un-Flip.
To see if you did it right, (and do this anyway) walk leftwards again. You should be behind the stand.
Now, flip again. You should now be doing a flutter-kick with a "2" sign above your head. Hold left and press 2.
If done right, you should be in a black void of nothingness.
Added by: Boometh Aug 14th 2009, ID#3026