Please note first and foremost: Unlike in the full Rock Band games (but like the other track packs), you can NOT use DLC to get this achievement.
The easiest songs to get this on are The Joker and Let Love Rule as they are both ranked in the Apprentice tier in RB 2. Of course, you may have luck on other songs due to your familiarity with that track and/or your skill level.
Just a couple of general rules about going for flawless drumming:
-It's easiest to not use your overdrive as the drum fill sections often replace the more tricky sections of the song.
-You do NOT need to FC (full combo) the song. It's totally fine to double tap so long as you actually hit all the notes, so don't restart right away because your combo gets broken due to hitting the drum pad one too many times.
-Practice, practice, practice. Eventually you'll get the coordination and pretty much memorize where your hands and foot are supposed to be and when they're supposed to be there.
If you have anything to add (like a tip or another song suggestion), just say so and I'll update accordingly.
Good Luck! :)