1] When the fight starts, go to a corner.
2] When the opponent approaches, just block and counter punch. Swaying from side to side to avoid punches gives you a good opening too.
3] The second your opponents punches land is the perfect moment to throw a punch back. If you hold R2, and you land clean, it's most likely to stun them.
4] Repeat this process, just stay in a corner and have the opponent come to you, then counter punch.
What not to do:
- Don't button smash, your fighter's stamina will reduce dramatically, and your block won't be effective.
- Don't get in a brawl with the opponent, that also will reduce your stamina.