I Study English

Another question about English.
I always find the same struggle when trying to express sentences like that.
The use of reflexive when talking about a third singular person.

This is an example and how I expressed it:
Each person represents himself through his way to address others and his behaviours.

As we are talking in general about a person whose gender we don't know, this time, I used "himself" masculine, to do the thing brief and bc in my mother tongue, we use the masculine over the feminine.

Other times, I use both: a person represents him/herself. A truly lost of time, especial in oral communication.

Which one would be moré acceptable?

And finally, is there also the possibility to use the plural in the reflexive pronoun even when the subject is singular?
Something like that?
Each person represents themselves.