There are many areas throughout the game to perform this action, but dont' forget about it. There are many falls that won't unlock this achievement, so you may need to use some trial and error to find an area that works. You will be introduced to the roll fairly early on. To roll you need to hold the :lt: while jumping from great heights.
Level Playoff easiest place i can think of watch video.
- You don't even need to make the second jump like the video shows. Just jump off and hold (LT) to roll and you'll get it.
http://www.youtube.com/user/NeedtoAchieve?feature=mheeThanks to Fizzmatix and Plasma SKX from Trueachievements!