General tips:

• Minority speakers lead to more minority attendees, which leads to more minorities doing awesome things, which leads to more minorities being well known, which leads to more minority speakers, etc, etc. Invite more underrepresented speakers, goddamnit!!!

• At large conferences, make child care arrangements readily available. Not all women have children, but the ones who do would be more able to attend your conference if it had the proper amenities.
• Likewise, don't hold every event in pubs or bars. Women with children will be excluded. Some women may also feel uncomfortable in an atmosphere typically associated with flirtation and boozahol.
• Have talks that are actually interesting to women
• More social events, replace old community, etc
• Call out sexism

• Uh, stuff

• I'm white and from Indiana, don't ask me how to improve this other than Tip #1 o_o