This isn't that hard. There are various employee groups around identities (Women in Tech, Asian Pacific, Black, LGBTQ, etc). Membership is not exclusive to those groups but also open to allies. As an example, I used to participate in the Women in Tech one at both Mozilla and at LinkedIn. Often I just listened, but I also helped organize a few events with them, contributed ideas for those events, and when they started a structured mentoring program I was one of the mentors.

There are also optional and non-optional hiring trainings that address these kinds of topics which you can do. I was a hiring manager for a while so I also spent some time doing some of these optional things to improve my chances of building a diverse team. This mostly included helping with sourcing candidates and a few times meant speaking up when I could see that identity biases were being used in evaluations.

But often just simple things are all you need. For example, when picking a group dinner destination making sure various culinary requirements are accounted for (either cultural or dietary) or finding team building activities that are inclusive.

I never once had an issue finding some of this to put on these perf reviews. Most of this is just under the category of being a good human who respects and values others.