How to Create logic

Using Arduino Project Guidance
14

Could plz tell me how to fix the floating outputs

This is the circuit we used with 4 O/P and I/P(repeated the same circuit 4 times)

http://www.seeedstudio.com/wiki/images/thumb/5/55/Arduino_Sidekick_Pushbutton_LED.jpg/400px-Arduino_Sidekick_Pushbutton_LED.jpg