well first you need to debounce the switch. you can do it in software or even hardware which ever you prefer.
then you need to make the arduino remember button state previous and current state compare them both if its not the same something must have happen. so lets say that if you push the switch and the arduino register it as a low then what you should do is if the previous high and current low increment switch press count.
ok now for the fun bit if the switch is 0 do something,1 do something,3 do something and lastly 4 do something. howver you need some programming wonder to make after 4 become a 0. i hope this help as a guide.
btw if im not mistaken ladyada have something along that line that you want to do
heres the link Arduino Tutorial - Lesson 5