More specifically: aim back, and where the left side (as you now face) starts to ramp down there aim for the spot where it starts to slope down. Full power.
I tried hitting the little floating island behind the start too to get a bounce but the ball clips through it.
What I did find was that you can use the purple spinning circle at the beginning as a teleporter to the one near the end if you aim at the wall opposite the spinner. Your ball will hit the wall and bounce back and up into the teleporter thing.
edit: I think the level changed?
I'm pretty sure Mr Dev Man messed with the power levels after I played, though, because it absolutely wasn't doable when I first tried. Surely.
It's possible. Done in 4.
Bounce it off the left wall in your first shot and you can land close to the end of the course.