There’s a learning curve here, so don’t be afraid. It took me about six oysters and a few choice vocabulary words to get the hang of shucking. Take your time and persevere.
If you’re choosing your own oysters by hand, select ones that feel heavy and full. Tap the shell firmly with your fingernail. This should make the oyster close up tightly. Don’t buy a hollow-sounding oyster, or one with a cracked or gaping shell. The smaller an oyster is for its variety, the tenderer its flesh will be.