Make sure your fist is tight and whenever you make contact your whole arm is directly straight with your hand. Put your whole body into it by shifting your weight, twisting your hips/shoulders, using your arm as a whip to transfer all that kinetic energy to your fist and whatever it hits.. Keep your wrist straight, hit with your first two knuckles. Make contact at the jaw line. Avoid throwing any wild swinging punches, keep everything inside. If he has his hands up, punch his hands and make him hit his own face with them. Once he starts dropping his hands start making contact with his nose, he'll start to turn his head and drop his chin, giving you a perfect chance to crack him in the jaw a few times. Get him moving backwards. It'll prevent him from being able to put much force into his punch without falling down. Once hes on the ground put your knee in his chest and a few more to his face until he stops fighting back. Keep your hands up with the tops of your knuckles right around your nose, a couple inches lower is okay if you're alot taller than him. If hes taller than you you want your knuckles to be right below your eyes. Stay on your toes, try to bounce a little to develope a rhythm. Move around alot. Know that if you don't give this your all, this person is going to beat the ever-living piss out of you. Losing a fight isn't the end of the world, but its painful and humiliating.
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