Things You'll Need
Instructions
Put the stretchy watchband around your wrist. Adjust it so that it fits comfortably, by pinching the place where you would like the buckle or clip to be. Make sure the adjusted watchband is small enough to stay securely on your wrist, but still large enough to squeeze over your hand. You should have a bit of extraneous elastic dangling down from your wrist. This is the part you will remove. Mark the ends of this part with a pencil.
Remove the watchband, and lay it on a flat surface. Look for the pencil marks you made, and cut off the extraneous piece at the pencil marks. Use sharp scissors for the cleanest and smoothest cut. Your watchband should now be in two halves, which must be reconnected in the middle to form the new size.
Turn your stretchy wristwatch inside-out, and align the two halves. Set your machine to do a tight 1/8-inch zigzag stitch. Stitch the two pieces together tightly and neatly. If your watchband is not elastic but a rubbery material that stretches, use industrial-strength craft adhesive or super glue to connect the two pieces, then clamp in place. Allow 24 hours to dry. Be careful when stretching it after fixing, because glue is not as permanent as stitching and can come apart if repeatedly stressed.
Trim loose threads, and seal with clear nail polish. Turn the watch right-side-out and wear it.