Use A and D or Left and Right to move left and right. Grab a green arrow power-up to unlock get the jump power, then press W or UP to jump. Collect more green arrows, and you'll be able to jump higher.

Collect all the power you need to reach the purple portal in each level. If you get stuck, press R to restart the level.

In later levels you'll also find power-ups to push crates and run faster. Collect and use them all to reach the finish!