If you want to become stronger and more invincible in life, some thoughts:

1. Stoicism is via Negativa, which means if you want to become stronger, figure out what not to do in order to become more.
2. For example, do not be petty. Even if you’re in the right. Petty means small. The goal of the stoic is to become non-small— Or another words, magnanimous.
3. Even if you’re angry, do not raise your voice, yell, scream or verbally attack or defend yourself. Better to stay silent, then say something out of anger and end up regretting it later, or hurting those whom you love.
4. If you want to grow a thicker skin, wear less clothing, even in cold situations. For example, when I was living in the East Coast and Providence, during the winter time I would see how long I could only wear a T-shirt for. Also, do not take hot or warm showers, even during the winter time.
5. Do not feel regret.
6. Do not feel fear. The less fear you have, the better.