First, you have to find a dolphin. You can get one on the black market, but the 1973 Marine Mammal Protection Act may get in your way if anyone finds out.
Place the wild or captive dolphin in a pen and separate it from its social group.
Create a strong bond with the dolphin by spending a lot of time with it.
In the U.S., the Navy Marine Mammal Program uses positive reinforcement to train its animals.
But, in the Soviet Union dolphin program they relied on fear and anxiety. To do this with your dolphin, drain water from its pen to wear down its resistance and put it in a harness and muzzle.
Deprive them of food to make them reliant on you and food rewards that they get for performing tricks — like killing enemy divers.
Put them in isolation tanks, because they don't like to be alone. That way, when you let them out, they will be completely attached to you. These are the most effective dolphin soldiers.
"I could take a wild animal and turn it into a good military animal in three or four months," military dolphin trainer Victor Grigoriev said in a History Channel program about the military dolphins.
Whatever you do, don't try to control them using electrodes in their brains — the Soviets tried this and through trial and error discovered the animals usually died. "There's just no reliable way to force dolphins to take orders like go to the left or go to the right," Vadim Belyaev said.
Equip your dolphin with a nose cone that contains a small clamp. Train the dolphin to swim up to the diver and nudge him with the cone, which tags him so divers could find him from the surface.
To train the dolphins, the U.S, military's Explosive Ordnance Disposal team would reward dolphins with sardines when they "killed" a diver pretending to be the enemy.