Grab your plastic bag and head to the beach's shoreline. Walk up and down the point where the shore stops. Pick up any shells you may see along your way and place them in your bag.
Observe any areas you see that seem to be pushing debris--whether that be seaweed, trash, rocks or seashells--toward the shore. Head to that area and wait for the tide to come in. Pick up any shells that may wash up.
Walk a little deeper into the water to see what lies on the bottom of the ocean floor. You only have to go about ankle deep. This will allow you to grab any shells you see before they're picked up by the motion of the tide. You have to act quickly if you see a shell, though, as the time between identifying a shell and the tide coming in is very limited.
Reach your hand down and feel the bottom of the ocean if the water is muddy or murky, or if the reflection is too bright to see to the bottom. Feel around for foreign objects. If you feel a lot of different textures, there's a good chance they may be rocks and seashells. A smart way to test is to sweep your hand along a few inches of the ocean floor, picking up water items you come in contact with in the process.
Go through the items you've collected in your hand. If you find seashells of any type, be they small or large, there may be some other opportunities below. If you only find small, pebble-like rocks and lots of sand, move on to a different area of the beach.
Test various spots in the shoreline as you walk. You can do this by sticking your foot a few inches into the water but not too far from where the shore ends. See if many items pass under your foot. This is done by testing whether any items, aside from sand, move swiftly with the shoreline when the tide comes in. If you have seashells or rocks trapped just underneath the sand below your foot, the current from the shoreline activity will forcefully try to pull them toward the beach.
Look around the beach, keeping an eye out for any children or kids who may also be collecting seashells. Move to areas that are closer to them where shells may be abundant. Be careful, however, to not completely invade their territory or take shells that you clearly see others reaching for. This beachside etiquette is especially important when it comes to children.
Visit any out-of-the-way or deserted areas of the beach. These may be untapped resources for shells.
Search the various crevices and cracks of any rock formations that extend into the ocean. Shells can become trapped in these holes when the current breaks on the rocks. Shells may also be hidden in seaweed or other items that are washed ashore.
