I feel almost anything would be good, at first - just to show I had human like sentience…

One small example would be “Don’t kill me. I have something to tell you”

Or if I had plenty of time

“Hello, I am the ant you can see. I was once human. To prove it, ask me a question and wait while I write the answer…”

Something like that

Once I’d been proven an “ex human” I’d probably demand to see my lord and saviour, Sir David Attenborough

Depends on whether I also get the knowledge on living as an ant, as a queen, in a colony.

Hardest thing would be predators.

I suppose the best I could do would be to find something to write with, like dirt or ink, and a scrap of paper, and “walk” some words along a page, hopefully notify a good human that I was an intelligent/human ant - and from there I’d be at the mercy of capitalism…