I got tired of being invisible at work - mostly everyone is catholic or orthodox, married, conservative. Since I'm married and my husband is catholic, I am assumed to be just like them.
So I started wearing a ribbon cuff bracelet with flags on it - the leather pride flag (black blue white, red heart), the rainbow diversity flag, the polyamory flag (blue red black, gold 'pi') and the bisexual pride flag (pink purple blue). I was sort of shocked that for months and months not one person commented, or even appeared to look at it twice. I figured even if no one at work noticed it, it was a good way to signal, to give other people I met a better glimpse of who I am. And a conversation starter, if they are into any of the above.
We hired some seasonal help - and one of them is a younger guy (who I had kind of a crush on) who started bugging me about what it meant. I told him he was too innocent to know if he didn't recognize the flags. He took offense (cause he really isn't that innocent, just young) and bugged me ridiculously until I told him what each one was. He admitted he had thought I was gay when he first saw it but was then confused when he heard I was married to a man. He asked some about polyamory, and I gave him the briefest sketch - his mind was utterly blown. "He [your husband] has sex with whoever he wants???" was pretty much the gist of his reaction. lol. So that was very embarrassing, but he's been calm and hasn't outed me to the rest of the office yet, so I suppose it went as well as it could have gone barring simply clamming up and refusing to tell him, which would have kind of defeated the purpose of wearing it anyway.
One of our regular seasonal people is a middle aged unmarried woman, who is very sweet, but also very catholic and very innocent. She started confiding in me the difficulties she's having with her current sort-of boyfriend, who she is in a long distance relationship with, and then started dismissing anything I said with an 'oh, you're married, you wouldn't understand'. I finally pointed to the poly flag on my wrist. She asked me to take off the bracelet and examined it. She asked what it meant - I only told her that one, as it was the only relevant one, and she asked even less questions than the previous guy. But it really opened her eyes that I didn't fit in the box she always assumed I fit into, and it seemed to really reassure her that she could talk about relationships with me, and I would try to understand and help, and that I might actually have relevant advice. So that went really well and wasn't embarrassing or weird at all, it seemed like she was relieved to have someone to talk to.
So basically I just let the bracelet talk for me; I'm still primarily in the closet, but the door is open, if someone wants to look in.