Don't Just Claim To Be An Ally...BE An Ally!
I once went to the gynecologist because I had a UTI. During my screening, I saw the nurses had an ally pin on their lanyards. Because I saw the ally pin, I thought it would be safe to come out as asexual... since I didn't feel comfortable answering many of the questions these ladies were asking of me.
Once I came out, I quickly regretted it. The ladies started harassing me about having sex, telling me it was a phase and I'll find a good man for myself someday... all that stuff. I was just super uncomfortable overall.