Are there ways that you are able to signal queerness?

People keep assuming my partner and I are two straight women, and it's just awkward sometimes. I know my partner would like if people saw us as a visibly queer couple, so I was hoping for tips.

Usually I try to engage in "PDA" like holding hands or kissing in public, but even that doesn't seem to always work (I have done this and had a waiter still assume we're relatives rather than partners).