After collecting your meal, separate the broken clams from the others. Leave the whole clams in a shallow pan of water for a day or two to siphon out the sand before steaming. Eat the broken ones immediately or use 'em for scup, fluke and striper bait, fresh or frozen. Walking them is just that. Walk along bars or the shallows, feeling with your feet for a firmness underfoot with a round shape.
Quahogs live from the tide line to the bottom of bays and coves.
Quahog rakes are long-handled and have narrow, concave tines, spaced closely together. Extend your rake and let it scratch the bottom, pulling it toward you, while you feel for the solid resistance of a living clam. Again, a little experience will teach you the feel of the thing. When you locate a clam, use the curved tines to root it out and lift it up to you. Using extension handles you can bullrake 15 feet of water from a skiff.