OK, you said you had two pairs left open. Each should be kind of twisted together seperately -- good to maintain that pairing if it's there.

On the RJ45 that's the typical end for a network cable, only 4 of the terminals are used for the Ethernet connection. With the connector laying on a table with the holder prong up and the side the wire enters, facing away from you; the wire order is: left most to right - white/orange, solid orange, white/green, nothing, nothing, green. Pin the ends thusly or connect wires to your receptacle so those will connect to your jumper cables that go to the computer and router. Of course, it doesn't really matter which color the wires in your buried cable are, as long as you get the right pins hooked to the same ones.