This one is fairly simple and can be gotten in the first dungeon. Once you've picked up an item - any item - press the 'Back' button, scroll down to said item, press the 'X' button then 'Start' and lastly, 'Y'. It'll pop within seconds of doing so.
Thanks to MACROSS SOLDIER who confirmed you don't have to pick an item up. As soon as you enter the first dungeon, follow the above steps to unlock your achievement.