I just sat on a MOC board. We interviewed a handful of female candidates. They all wore slacks, nice blouse and a few had on blazers or matching suit jacket with pants. It happened to be cold and rainy the day we did interviews. If they are used to heels, it’s fine to skip them. Don’t wear jewelry that is loud or wear any perfume. Keep it simple, smart, professional, well pressed, well groomed and she will be fine. Have a solid handshake and look everyone in the eyes. I can’t tell you the number or candidates who couldn’t walk in, shake hands, look us in the eye and say hi or introduce themselves.