check out true achivements site for guide..they have a video too.
www.trueachievements.com/a41466/lap-it-up-achievement.htm?showguides=1
Hey, that's my solution and my video .
To the OP, the trick is to take all the corners as tight as possible, as in getting your left hand over the 'pucks' (the black things on the inside the corner). Try get get green on the skate timings, but getting a few oranges or reds won't kill your chances. Notice I screw up a bunch in my video but still get the achievement easily.
Do Not Touch was much harder than this IMO. I made a video for that one too .
Here's the link to Lap it Up video on YT:
Link