It's not in bad shape, so I'd leave it as is. I sometimes clean silver jewelry, but rarely any coins. The best way to clean silver is electrolysis and it's easy to build one yourself; Chicago Ron has a good video on You Tube on how to build it.
A rule for coins: you can always clean off the dirt with soap and water, but NEVER use anything that would remove any existing patina. Removing patina devalues the coin.