Cat 5 is 4 twisted pairs, but you have to untwist the wires, reorder them as follows:

orange-white
orange
green-white
blue
blue-white
green
brown-white
brown

then align them all and jam them into an RJ45 connector without messing up the wire order, and then crimp.

We rewired our office last year, including punching down all 6 jacks at each desk. Boy was that fun.