Want to go snorkeling? The best opportunities are from a sail boat, usually a catamaran. 

Snorkeling in deserted cove from catamaran

The best way to go snorkeling in the Tamarindo area is an afternoon catamaran sailing tour. They'll take you to remote places known to have better visibility and more sea life. Along with the snorkeling and sailing, they also serve beverages and lunch. Passengers often share the fun with other passengers and party together. If you book a sunset cruise, they always stop in the bay as the sun goes down and play music. Here is an article about an actual sailing and snorkeling tour.

  If want to take your chances with visibility conditions and don't feel you need a guide, there are several locations close to shore.

- Take a sea kayak to Capitan Island in the middle of Tamarindo Bay. Conditions can be excellant when surf not too large, but often dangerous currents present. 

- Bahia Pirates and Playa Minos are both within a 40 minutes drive. Semi-sheltered, totally doable.

- Snorkeling in front of the Diria Hotel is pretty good most days near the rocks on the south end of the beach, but dangerous currents.

- When the visibility is good, the northern end of Flamingo can be interesting. It is renowned for white tip sharks and rays.