Help me come up with something

So, I am going to get right to the point of this post.

I'm biromantic, asexual, genderfluid, and polyamorous. I am not out to anyone besides the 5 people that I told and knew I could trust, and now 1 other person where I feel like a mistake has been made. This one person is part of the community, which is why I thought they were safe. However, there is a recent situation surrounding this person and my spouse (and spouse's family). I fear that if they do not get their way, they would out me to get back at us. If anything happens, I want to have something ready to be posted so I can tell everyone first before this person has the chance to say anything.

Problem is: I have NO idea how I want/should do it (text post, video, photo, etc.) Any suggestions would be appreciated