If you've recently lost or gain weight and your ring no longer fits, there a few ways you can resize it yourself. Getting a ring resized professionally can be expensive, so if you only want the change in the size of your ring temporarily -- if, for example, you just want to wear it on a different finger -- there is a way you can do it without spending much money.
Find two small, smooth beads that will sit between the inside of your ring and your skin to make your ring a little more snug. Look for beads that also match the colour of your ring.
Dab some epoxy on a bead and press it against the inside of the top of the ring. Attach another bead next to the first one.
Wait 24 hours for the glue to cure all the way before wearing the ring.
Position the jaws of a pair of sharp bolt cutters in the middle of the bottom of the ring. Squeeze the handles slowly to create a clean break in the metal of the ring.
Gently pull the two sides of the ring apart to make it fit, but not so far that the ring becomes deformed. You should only do this if you need the ring to be slightly bigger, and if the ring isn't made of precious metal.
File the sharp corners of the cut metal so that it won't scratch.