The tool needed is called an IDC/Punch-down Tool, the cheaper variety look like this
But don't trim the ends of the wires off, the more expensive version looks like this
And has a pair of cutters to trim the ends of the wires off, note that you don't need to strip any of the wire, the IDC connectors have internal "blades" which pierce the wire when you press it in, this can also be done with a flat-bladed screwdriver but the connection isn't always that great.