Instructions
Suspend the yo-yo at the end of its string.
Pinch the string a few inches above the yo-yo. Spin the yo-yo to the left -- counterclockwise, looking down at it -- to unwind the string and open the large attachment loop.
Hold the loop open wide with your fingers and slip the old string off the yo-yo.
Twist the end of the new string with your fingers to open up the attachment loop. Slip the loop over the yo-yo and onto the axle.
Hold the yo-yo and gently tension the string to cause it to retwist and close the loop.