Put on some oyster-shucking gloves (yes, you need them), then hold the oyster in your palm, rounded-side down.
Find the groove in the pointy end. Push an oyster knife into the groove until it’s stuck. You should be able to hold the oyster on the knife like a lollipop.
Twist the knife like a key in a lock to pop the shell open. Gently slide the knife in and pry off the top, cutting through the adductor muscle.
Run your knife around the edge of the shell to cut the oyster loose from the bottom, being careful not to mangle the meat. Done!