If using fresh bread, you can grill the bread slices along with the salmon and then cut them into cubes. Alternatively, cut bread into cubes, place on a baking sheet and bake at 300°F until dry.
To skin a salmon fillet, place it on a clean cutting board, skin-side down. Starting at the tail end, slip the blade of a long knife between the fish flesh and the skin, holding down firmly with your other hand. Gently push the blade along at a 30° angle, separating the fillet from the skin without cutting through either.
To oil the grill rack, oil a folded paper towel, hold it with tongs and rub it over the rack. (Do not use cooking spray on a hot grill.) When grilling delicate foods like tofu and fish, it is helpful to spray the food with cooking spray before placing it on the grill.
Fish on foil: Fish that flakes easily requires a delicate touch to flip on the grill. If you want to skip turning it over when grilling, measure a piece of foil large enough to hold the fish and coat it with cooking spray. Grill the fish on the foil (without turning) until it flakes easily and reaches an internal temperature of 145°F.