Just a handful of things that were helpful to me, or that I developed with other allies, while working at Etsy.
Resources for allies
Recommended Reading for Allies by Toria Gibbs and Ian Malpass (Code as Craft)
Giving good feedback
Study: Women ask for feedback as often as men—but are less likely to receive it (PDF, look at page 14)
Thank your local ally: Etsyans' favorite baked goods