In your sketches, suggest you scan switches every 50ms or so.
This can filter out bounces.
Handle switch readings with change of state/position detection.
If a switch has changed position, from the last time it was read, do some action based on the level the switch is at. Then note the new position of the switch.
If the switch changes to the opposite state/position, note the new state then do some action etc.
There is an example that comes in the IDE you can refer to.
Also, see the SwitchManager example:
http://forum.arduino.cc/index.php?topic=350287.0