Repeatedly press S during the demonstrationsequence, when Germ is eating the player.

Press [Esc] + R during game play. Entera number from 1 through 8 to select that level,or enter $ for additional levels.
t, sahp tecrfpt nulafabtb hwtue

Execute the following DOS commands.

22D5:

900 or 7FD or 2083:EA EA