One thing I have learnt about criticism is that it is generally done by people who don't have a lot going on in their own lives. They judge and criticise others to make themselves feel better. If I am criticised I generally say "I appreciate your opinion, but I prefer to do it this way".
Listen to the criticism first and before getting defensive, decide if it's constructive or not. Often criticism can be something you can learn from and make changes especially at work. However, I think it should always be given in a consultative way.
It depends who it comes from and whether you were looking for criticism at the time. If it's criticism from total strangers or people commenting on something that's none of their business (some people just love commenting on others' parenting, for example) I try to ignore it or give a "thanks for sharing" which can be neutral or dripping with sarcasm. If it's from an employer, or someone reading my writing, or a caring friend I try to take it on board.
Over many many years I have been criticised for one thing or another.
I take a good look at 'what' it is they are saying.
I go down deep inside and look 'if' they could be right.It takes time to learn how to do this.
By removing yourself and looking as if you were seeing another person.
In this....you have to work fast, before your mind takes over and you 'feel hurt'.
Something like a quick evaluation of what just happened.
It can save you a lot of grief later, and we become in my opinion a better person.
Even if your not in the wrong, it is a great tool.
If I am wrong, I see it...then fix it.
If I feel I am not wrong, then I am very polite....but always point out the reasons 'why' I believe they are wrong.
NEVER loose your temper...that is a big no-no, if you ever want to have credibility
Confidence to know yourself, act upon it, and not take it personally.
Once people see they have affected you....then you haven't got a leg to stand on.