**NOTE: I'm not sure why I put this one on first, because it's more complicated. You may want to scroll down and start with METHOD TWO.**
Cut two pieces of wire long enough so they can almost make a full circle (top to bottom) around your container.
Fold each piece in half and loop them together as shown.
You can cut the wire if it's too long, or to your own desired length. Make sure to keep some length for added support, though. I'd say at least one inch into your container at minimum.
Pinch closed with needle nose pliers, and repeat with other end of wire on the opposite side. You should have an upside-down U shape over your container. Carefully twist the top to form a small twisted circle for the next wire to pass through.
This picture is hard to see, but I connected the ends of the wire on this glass dish side-by-side instead of on opposide sides and looped them together at the top.
Cut a length of wire long enough to circle the mouth of your jar about 1 and a half times.
Twist a loop in one end, and hold it in place under the lip of the jar, pulling the wire around until you reach the opposite side (180 degrees from the first loop) and make a second loop.
Next, pull the wire back to the first loop (creating a full circle under the lip of the jar) and hook the wire around the first loop. Pinch closed with pliers.