Know your enemy. Know their nature. Understand their strengths and their weaknesses, their effectiveness and their vulnerabilities.
Know yourself, and train yourself to overcome your own weaknesses. Sympathy or hesitation has no place in the fight against zombies. Don’t waste your time thinking about what they once were. They’re not human anymore. They are not fickle in their objective; they have but one. A zombie commits 100% to their objective and will not stop, no matter what. Feeding on you is the only goal they have. You are their next meal, and their hunger is insatiable.
A zombie’s strength lies in it’s persistence, it’s mouth and, if still in tact, it’s two hands.
A zombie’s main weaknesses are a lack of coordination and problem solving abilities. Further weaknesses are dependent on the level of decay of the zombie.
A zombie is predictable. They are driven by the primal need to feed, and nothing else. As long as you’re aware of your surroundings and are expecting an attack from any angle (though easier said than done), you can successfully defend yourself against a zombie attack.
Again, a zombie’s main weaknesses (coordination and inability to problem solve) are always a factor, yet the degree to which these weaknesses are a variable in combating a zombie, relates to their level of decay.