Writer and activist Claire Light was recently discussing ways for journals and publishers to attract women and writers of color to submit to them.
I've got my own take on it all often boils down to DIY instead, an approach that emerges from experience, but I can see some writers are deeply attracted to the idea of someone like Random House, DC, Copper Canyon Press or Kaya giving them the seal of approval. Some of the big points Claire suggested for editors that I would particularly endorse include:
Diversify your masthead and staff.
Incorporate inclusive language that actively invites writers of diversity to submit.
Have in-person visits to open mics, readings, classrooms in diverse communities to get them familiar with you. Or: To be read, be seen. To get submissions, be someone to submit work to.