I am always myself. Sometimes different versions of myself, but always myself.

Growing up a military brat I moved a lot and learned to adapt and hid who I was for fear of rejection (bio dad was also absent from my life,hence the fear). I always admired the Cyndi Laupers & Boy Georges of the world though, so by the time social media became a thing and I learned how to use it to communicate with my nieces, the introvert in me decided to be more open about who I really am. Having said that, I do think the current political climate begs me to be cautious again, in the interest of survival and the ability to fight another day, something vital for a liberal minded diplomatic type living in a predominantly conservative Christian area.

This is a deeper question than it appears.

First there is the issue of the self. What is it?

In this instance I assume it means being 'authentic'. But since our personality is a product of our life experience and our interactions with other people, how do we know when we're being truly 'authentic'?

We can try to resist being swayed by those around us and make an effort to be closer to our authentic selves. But it's impossible to be 100% ourselves. That would require living in a vacuum.

The only thing that stops people from being themselves is fear. And those fears are always subjective and personal to the individual.

Growing up, i always felt alienated from those around me, even though i had loving parents and have had small groups of friends all my life. So I tried being the chameleon to fit in, and since i was a good actor, this worked for a while giving me most of what i wanted. But by my mid-20s, avoiding who and what i really was had become exhausting, old, and boring.

Once I confronted my specific fears, however, I begin appreciating who i was at my core and what i could bring to every table i decided to sit at. In fact, I relearned how to replace my accommodating behaviours with assertive ones. And it worked, which is why 45 years later, i can look back to a wonderful life which continues to bring me joy, daily.

You asked for advice, but since my father used to say "free advice is good for nothing" this is my suggestion for people to consider.

Confront your specific fears, once you know what they are. Then do what you need to do to be yourself despite your fears by jumping in with both feet. What's the worst that might happen.

If it felt good, do it again; if you have regrets after, learn from the experience and don't do it again.

That's how i've lived my life without regrets, but with lots of learning.

I tend to be me no matter the situation, which explains why I don't get invited out much.

I don't know how to be anything else. That anything else includes allowing myself to be intimidated by others and I do modify my behavior in those circumstances. But that's ok. It is what it is.

Preserving that sense of my own personality means a lot to me however that isn't a valid reason to not adapt to changing circumstances.
Classic example would be a job interview, where if I choose to be myself they are definitely blacklisting me

its pretty hard not to be yourself.

When you learn to be yourself you will not want to be anybody else, that is when the real control of your life by you begin.

I am always myself but I also remain quiet on certain topics if they come up.

I'm always me. Some situations I don't handle as well as others -- I'm still me. Working on change sometimes works and sometimes doesn't. I would say -- do not worry about your failings, concentrate on your successes.

I don’t think there is one single “you” in any person. We change a little or a lot depending on situations and circumstances. I am different at work than at home, and when out in social situations I’m different from either of those...

I do my best to always unapologetically be myself, though subconsciously I am too aware of when my personality is too much for certain crowds or what have you and i will sort of put a pillow over that. I like to feel out a space before I let my Suzi light shine at max. I will never waiver from my opinions and standings because of popular opinions or standings around me though.

Yes & no, my honesty tends to be misinterpreted as disrespect towards nationalistic government employees so if I'm in court or something I tend to be less honest or more quiet than normal.

You are being yourself. When you are in the company of smarter people it is intelligent to just listen and let them do the talking.

You are indeed wise beyond your. Years young lady. ?

Sounds like you are assessing your environment and altering your behavior accordingly. - - Nothing wrong with that as some environments must be socially navigated differently.

I tend to shine when surrounded by brilliant people and or atheists but I often remain less outgoing when surrounded by delusional theists as we often have significantly different views on most topics.

You ask that like I have a choice ...

Sometimes my angry self shows up...like me only ANGRY!