Don't die. You have 3 lives and a stock of bombs. Bullets come at you from all directions.
Try to let the screen fill with as many bullets as possible and then press the bomb button for mega points. You get bombs back every now and then, -- maximum of 3 -- so don't get _too_ greedy!
Controls:
Arrow keys - move
Z - hold this to move half speed
X - drop the bomb and cash in the bullets for beaucoup points