How to extend usb 2.0 cable with 4-wire phone cable.

1. cut the short usb cable in half.
2. connect the wires to the phone cable.

Make sure colors are the same on both ends.

If you connect red usb wire to brown phone cable, 
make sure you connect brown phone cable to the red usb cable on the other end.

You do not need to solder it, just wrap the metal ends of wires tightly, and use insulator tape.
Test it on something cheap first, like keyboard.

You do not need to connect shielding wire (5th one),  if there is one.

You can make 5 meter or 16 feet max length cable. That is total length.

Devices that need more power like webcam might not work with this cable.
Keyboards will.

Also here: