Instructions
Proceed cautiously through the level. Despite its light-hearted design, the game features some very difficult sections, especially at later levels.
Memorize certain traps, obstacles and other unexpected pitfalls. You don't have to ace the planet on your first playthrough. Take note of particularly nasty parts of the level and return to ace the planet when you know what to expect.
Don't try for 100 percent completion and an ace in the same playthrough. Trying to collect all of the prize bubbles in a level can significantly increase the stage's difficulty. Collect the prizes and return to ace it when you're more confident about the layout of the level.
Complete the level without dying once. This is the only criterion for acing any planet in Little Big Planet. Each stage in the main game has a special set of prizes available after you ace an individual level.