An amazing game!
I only just completed it with 1 life left, here is a guide:
First, there will only be music, nothing to worry about
After a few seconds, cannons appear and shoot at you, try to keep as many lives a possible
Next there will be pistons, wait until they vibrate, then move away
The top set of cannons will join these after a while
The pistons will go away, but the bottom cannons will join the top ones.
A yellow cannon will appear, hug the top of the screen and avoid the particles
A green cannon will come next, when it fires, move round in circles until the missile has gone.
A Packman monster will arive now, just go in circles to avoid it.
The last part is the hardest, the pistons and the two sets of normal cannons will come. Dodge those and you will be free.