This is found on level F1-3: Snapping at the Heels. Underneath the track where you'd normally drop your time field is a toy dinosaur.
Hit

to get under the platform, then

to ride the thin end down towards the laser. Once it hits the laser, fall off to the left side, then

to brake before hitting the next laser. Approach the platform, then let it move you towards the laser. Wait as long as you can,

to slide back down the wall, then mash

and hold right.
Using the circular saws over your head to align yourself, stand under the third one, then press

to fall,

to apply the brakes once you're past the platform, and

to right yourself.

on the dinosaur gets you the achievement.