Enter the code at the high score screen:

Code - Effect

GIVEMECHEAL - Extra Lives
GIVEMECHEAY - Have balloons while falling
GIVEMECHEAO - Have parachute while falling
GIVEMECHEAA - Hold Fire for rapid shots
GIVEMECHEAI - Invincibility
xx.QCUMBER - Jump to Level xx where xx is between 00 and 42
GIVEMECHEAM - Level Skip