1) Keep Jewelry clean and dry! Always remove jewelry before showering, cleaning or swimming - do not wear into pool, hot tub or sauna. 2) Keep skin clean and dry. Always wipe jewelry down with cleaning cloth after wearing it before storing. This aids in preventing tarnishing. 3) When storing - seal them in plastic bags (squeeze all the air out before sealing). Also, it may help to store with a no tarnish strip. Exposure to air, chemicals & moisture is what causes jewelry to tarnish. 4) Do NOT use liquid jewelry cleaners. 5) For changing the snap - pry out using the pick tool by placing tip of pick between the snap and the accessory and twisting until the snap comes loose.
You may also try applying clear nail varnish (polish - NOT top coat!) on the jewelry. I have seen mixed reviews on this so try this at your own risk. I have not seen where this has hurt the jewelry but rather that it has flaked off. So, if I was to try this I would do this with a very light coat and just reapply periodically as it is noted that it wears off. Again, try this at your own risk! This is merely based upon research / information that I have found available and in no way endorsed by myself.
If interested you may request to become a member in my closed group on Facebook to see alternative jewelry and specials! See new jewelry received in before the public does!