Head guard and body guard have different jobs
The developer confirms different guards for your head and body. The useful question in practice is which target is threatened, not simply whether you are holding a defensive input.
For a focused round, watch the opponent and name the target to yourself before choosing protection. Review the outcome without assuming that a guard stops every attack or has a particular damage-reduction percentage.
Practice the slip as a separate skill
A slip is listed as a way to evade punches. Keep a slip-focused practice round separate from a long offensive sequence so you can tell whether the defensive action worked.
When an attempt fails, inspect what you actually saw: the incoming punch, your action and the result. Exact invulnerability windows and directional rules are not established by the official description.
Treat fatigue as part of your decision
The official description says becoming tired slows you down. That makes the stamina display relevant before the next exchange, not only after you have already attacked.
Editorial drill: compare a round where you act continuously with a round where you pause and observe between exchanges. Watch your own stamina and responsiveness. Do not treat this comparison as a fixed recovery formula.
A quick defense diagnosis
After a difficult exchange, choose one question. Was the attack aimed at a different target than your guard? Did your slip attempt visibly miss its intended moment? Were you already tired before acting?
Pick the question you can actually answer from gameplay or a replay, then make it the next practice goal. If the replay does not show a detail, leave the conclusion open.