• To know in a short interval where your Sprint and Grab keys are.
  
• Some experience in the in-game gym class is optional and helpful.
  
• A line of sight to your target.
  
• A little bit of health as a buffer; the more the better.
  
• An escape plan.

1. Begin by mentally marking your target. In some cases you may already be in combat - in which case the choice is already made - pick the most dangerous one of the bunch.
2. Mash sprint as you run towards your target. You don't need a run-up at all, just to be sprinting.
3. This is the tricky part. As you approach your target, stop mashing sprint, and hold Lock-On and press Grab. Jimmy should, in one swift move, floor and mount most opponents, excluding the larger Jocks, Russel and Bif. For the larger Jocks, gym class will be essential to floor them. Either way, get them on the floor, and have Jimmy mount them.
4. Now start mashing Punch. We're not here for heavy strikes. We're making like Gene the God Hand here. Fast, quick, easily cancelable strikes. You might take off a bit of his health this way... Keep wailing on him until he pushes you off...
5. He just activated your trap card. THIS IS EXACTLY WHAT WE WANTED HIM TO DO. Because of how the fighting animations work - quick background, like all animation, motion in this game is split into frames, like a fighting game. And like all fighting games, attacks have startup, active, and wind-down frames, and can cause hitstun and blockstun. It just so happens that the number of frames it takes for Jimmy to go neutral and throw another punch is less enough than the wind-down of the floor recovery. In other words - we can start landing effective hits before the enemy has recovered from pushing us off. Now, if you have the third charged punch, or the full five hit suite, you can unleash them for a torrent of knock-down mount and punch awesomeness. If you don't, you'll be tackling the smegger again. It works though.

It's a life saver against the ire of the tougher Greasers faction especially since up to then, you've had middling experience with the school's punching bags, namely Bullies and Nerds. It works against the Jocks and Preppies in limited capacity as long as you find a way to force the tenacious lunkheads on their rear.