What is the 101 on self-defense? Blocking or the evasion from attack. People having years of martial art training may get panicky in a self defense situation, and they can become tense and can't block or evade an attacking punch or, usually, continual punches; or they can get over-excited and start punching people when a fight can actually be avoided! Why do they start punching people? Because they're afraid that they may be punched, so, in panic, they attack first!
There are loads of courses out there teaching the art of self-defense, from traditional martial art to new-age gyms having "experienced bouncers" as their coach. To be honest, no one can be fully trained to defend oneself against all possible attacks (for one thing a smaller guy may, unexpectedly, carry a sharp object!) Therefore, the best strategy for an average martial artist is to train on the basics and, knowing one's limitation, will be humble enough not to stir up a fight, but will be relaxed enough not to panic and therefore will have a better chance of staying (relatively) unharmed under attack.
I like this Bas Rutten's punch blocking video on Youtube. There are a number of important points being raised:
1. Try to do minimum block rather than overly deflect the attacker's punching arm. And therefore able to quickly move back to the original guarded position after the block (i.e. not to "invite" the next punch, by giving an opening to your opponent).
2. Stay calm and relax (confidence comes from knowing that one is always in the safest guarded position).
3. Move JUST away from the punch even with blocking (your attacker's punch may be too quick for you to block: ref- Bruce Lee's unstoppable punch).
4. If possible, better move away completely from powerful hook at the head (again, for the sake of "on the safe side")
5. Only do counter-attack AFTER a successful block ("smart" approach of blocking and striking in one-go will be too risky!)
6. Look straight at the attack (and in a guarded position) at all time (well, unless you're a good grappler shooting at your opponent's legs to tackle him!)
7. Putting one's body weight behind each block for power (ref: zhan zhuang's muscles-as-one 肌肉如一)
The above strategy is actually a humble strategy for maximum safety. Only through being humble and putting oneself in the safest position, one can feel relax and be able to have a better chance to stay (relatively!) unharmed in a self-dense situation. But then again, nothing is foolproof.
Corollary: when one feels safer, in better control of the situation and consequently more secured, one is in a better position to negotiate out-of a confrontation while insisting on others respecting one's rights, for the benefits of all.