This level is pretty difficult for the less-skilled players. The platforms are akwardly placed and pretty close to each other. Also, you might accidentally change gravity, which will disorient you, causing you to fail the level.
After you start the level, go straight until you fall and then land on the lower platform. Right after you land, jump up to the platform above you. Then, just stay on the upper platforms until you see the bonus on a small platform.
This level has been named Altostratus, perhaps because the formation of platforms looks like the cloud formation Altostratus, however the platform formations more closely resemble the cloud formation Altocumulus.