[B]If you have a spare USB cable that you don't care if you never use it again:
Cut it in half, and strip the sheath from the cable on the end that usually plugs into the computer
Cut the white and green wires off (or white and blue)
There should be two remaining wires, red and black, strip them so there is just the actual wire (the metal strands)
Now look at your battery, there will be four notches, in it, one will be marked (+) and one will be marked (-)
Fold the wire inhalf from the red wire so it is a bit thicker, and just twist it a bit so it hugs itself, SLIDE THE RED WIRE INTO THE SLOT MARKED (+)
Fold the wire inhalf from the black wire so it is a bit thicker, and just twist it a bit so it hugs itself, SLIDE THE BLACK WIRE INTO THE SLOT MARKED (-)
Use some tape to make sure the wires don't touch each other and are secured in place, then, plug the USB plug into your computer
the battery will start charging, it will take about 2 hours to fully charge, it is almost impossible to overcharge the battery as they have a built in overcharge protection circuit.
*intermission music*
~ about 2 hours later ~
Congratulations! Your battery is charged! You can now do stuff that you need a charged battery for.
WARNING I'M NOT RESPONSIBLE FOR ANYTHING EVER PERIOD[/B]