In a fight, there is a fundamental difference between boxers and everyone else. The guys who have trained are different. If you hit them, they don't flinch. — Julien Smith
In this age, getting the information is not the problem. The flinch is your real problem. And more information won't help you.
What is the flinch?
Anything that supports the status quo. The initial rejection whenever you want to do something. Whenever you want to try something different.
Evolutionary speaking, the flinch is an instinct to protect you from the unexpected. To protect your eyes and neck.
You were born with some fears to keep you safe: falling, abandonment, loud noises, etc.
But, you are safe! You don't need to flinch anymore. Stop seeing everything as a threat.
Mistakes are not final. Pains and scars are both temporary and part of the path. Stop defending yourself.
Your privileged-world problems become the bear, and you treat them that way. — Julien Smith
Test your own limits. Learning from another person will only make you learn other people's limitations.
Be proud of your scars because they are part of your path.
Step into a cold shower. The discomfort will only last a second.
Get lost. You will be able to get back home.
Hold a mug in your hand and then drop it. Being able to let go is more important than anything you own.
Do the opposite of your habits.
Speak to the next stranger you come across.
Read things that are too difficult for you to understand.
Challenge yourself to do things that hurt, on purpose, only to show yourself that you can.
If you're not able to do any of the things above, just look at your failure. Don't hide from it. Realize that all it takes is a single moment of strength. Every time you are able to do it, you get stronger.
The goal isn't to get used to the pain. It's to understand that you can do things despite the pain.
Overcoming the flinch will provide you with an ever growing set of experiences that you can call upon.
You need to decide what to fight for and, if it's worth it, don't even let the flinch to appear.
Judging if the flinch will help you or not is not the point. You can only evaluate things from experience.