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

POKE 9521,0 
Unlimited lives:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 9523,170 
Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC commands before running or restarting the program. 

POKE 9251,44
POKE 9523,170 
Cheat mode:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 12761,44