There are several places where this can be gotten, and i'd recommend a small driver such as Alex Kidd to give you more time. Simply approach a ramp as fast as possible, then once in the air hit LT to do a trick. Repeat this three times, then once you hit the floor you should have a red boost and Achievement Unlocked.
Make sure you successfully pull off the third trick however, otherwise you wont land successfully, lose your boost and not get the achievement.
Jumps that spring to mind: (All of these were done with Alex Kidd, not sure if that makes a difference)
Shibuya Downtown - After drifting around two corners from the start line, you will come to a tunnel, on either side of the tunnel is two ramps up, take one of these and follow the path round to a boost ramp infront of a billboard. Break through and hit the 3 tricks (Doing this as Beat also unlocks another Achievement)
Ocean Ruin - After going underwater, near the end of the tunnel you will be boosted into a jump that will give you ample opportunity to land 3 tricks.
There are probably other tracks, but these two are the first that spring to mind. Id recommend Shibuya Downtown to get the other achievement.