Unlimited lives:

Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 13270,173 

Unlimited shots:

Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 14022,173 

Invincibility:

Load or reset the game, then execute the following BASIC commands before running or restarting the program. 

POKE 13603,169

POKE 13604,0

POKE 13605,234

POKE 13606,234

POKE 13607,131