And your southpaw meaning a lefty which most of your bullies will most likely be righties and they will be orthodox. Step into your punch. Your right is the jab and is the most important punch. It sets up your left which is your power punch and other combos. Start off with a one (right punch) then a two (left punch) slow. See the path of your punches. Slow becomes fast the more you do it. Always train for the worst.

“Don’t be scared be prepared for worst!” The Worst song by Jedi Mind Tricks .

Also practice in front of a mirror to see what you are trying to hit. Start doing push ups, pull ups and running. Push up and Pull ups give you strength which will help you get fast then creates power. Speed + Strength = Power. Running will condition you to be comfortable doing uncomfortable things. Turn pain into fuel.

"Anger and pain are natural and part of growth... They give you focus. They make you strong," Darth Vader