How Snaps work
To remove the snap from the jewelry base, simply place your fingernail/pick under the first rim of the snap. Do not pull from the top decorative area of the snap (roses or pearls or rhinestone, etc) or from the jewelry base, as this will cause damage to your snap and/or jewelry base.
The snap will detach from the base easily and will be ready to be replaced with a new design. The first time you put a snap into a jewelry base (necklace, bracelet, keychain, etc) it may be tight so just give it a good try.