After starting the game, slow down the speed to the lowest settings then click Game Menu. A list of options will appear. Click Enter Code and type one of the following codes. Then do what you want and speed up the simulator as you want.

Effect	Code
All items unlocked	indiegamerchick
Get a new contract tomorrow	snickerdoodle
Increase working hours for employees	balbin
More birds	all these birds
Sniper Mode!	kill the birds