This is a hard thing to do but if you do it right it's a pretty cool glitch.
On the last lap when youre under the finish ring you can float away.

Right when you land on the ring you have to grapple down and the screen will be in a fixed place and it will say YOU WIN! But you can still move.

To make the screen move again you have to get carried by the fly dude by falling for or hitting the acid.

That will make the screen move agian so you can see what your doing
But as soon as you land on the finish ring you wont be able to move
If you jump you will start floating as soon as you land.

You will keep floating until you jump which will make you fall back to ground.

Its easier on the easy street levels.

If you float high enough you will float out of the screen and soon after it will reset the game.

This will not damage your game in any way and it's really fun !