A few activities have further means of ensuring people aren't put through unwanted experiences there.
1) A long time ago CUSFS (Sci-Fi) dealt with the matter of certain people dominating conversations or interrupting others' contributions by adopting the convention that only the person holding the ceremonial ball of socks should speak.
Other members could put their hand up to appeal to be the next person to be passed said ball of socks.
2) You've also seen mention of a CakeFaerie badge. While worn, this has the magical property that another CakeFaerie spots the wearer and offers them Surprise Cake.
A person who does not wish to be approached during a particular outing or on a particular day simply doesn't wear the badge then and so isn't approached. This is the simplest kind if do/don't approach signalling system. It has one word: the CakeFaerie badge (meaning "meet me with cake") as well as the blank word: not wearing it (meaning "no meeting people with cake at present"!).
By this token, the ball of socks is a one-word badge saying "holding this ball of socks means that it's my turn to speak", to the blank word of not having the ball of socks.
The ball of socks example is Society meeting based and involves a total of one label. Moreover, in a meeting with Socks and Fusion/Fission, there could be a box of balls of socks, so that each conversation contains precisely one.
On the other hand, the CakeFaerie badge can be worn city-wide during the CakeFaerie Hours of 10 am to 9pm, so it is a Ractor variant of a badge. Other examples of Ractor badges include team badges and team facepaint.
While it's useful not shooting your own team or knowing who is a CakeFaerie and currently willing to receive cake, the first big breakthrough with Badges/Headbands/Sashes is as follows.
3) The LARP (Live Action Role Playing) finger in the air. While this means "I'm Out of Character so ignore me entirely", this also implies "don't in any way impede me if I'm suddenly leaving the area". By this, it can cover sudden anxiety panic attacks or other changes of mood.
4) As the main item on this page, Meet-ups for people with Autism adopted the following three-word dictionary in the form of "conference badges"
Red with a Black Square for "I don't consent to any conversations that I don't initiate."
Yellow with a Black Triangle for "I only consent to people I already know talking to me".
Green with a Black Circle, for "whoever wishes to start a conversation with me is welcome to".
* Centre our Autism Button here, which is to have all three of these present on it *
There involve shapes as well as colours to accommodate the colour-blind, and the badges are large-print to help with the partially-sighted.
There could also be a rule not to start conversations 'from behind' if one does not know what badges the people in question are wearing.
Another possibility is to wear badges on one's back as well.
See here for more advanced points about communications badges, e.g. for parallel use by Survivors or for many intersectional uses.