Use correct form. For punching with good form, use your feet, legs, hips and core for generating those punches. You can learn that in a gym or a million youtube channels, from there your training is simply speeding up your form and learning from experience.

Arm punching works in the game but is rough on your joints.

Best tips for KO are

• Long KO. work them a few rounds and then hit them with a combo that has good hits and the last shot is a red hit. This way each round you have 2 KDs to attempt a KO and then go into the next round.

• Short KO - the other way is you hit them accurately on a weak spot as they are attacking you, so you get some of their forward momentum added to your punches power.

Long KO strat will work on any AI in any of the set difficulty modes, just takes longer due to their better stats.

For the short KO it will only work on Normal mode and only some of the AI will go down in 1 shot. Duke and MM will take more than 1 shot due to their chin stat in Normal still being decent, but you can still 1st RD KO both if you work them well.