I've worked closely with folks who have previously interviewed for MA Experimental Psych and MA and/or MEd Counselling (i.e., I do not have direct experience, but consulted with these individuals for my own interviews in clinical). The common observation is for interview days, business casual at a minimum and depending on comfort levels, tie and a smart jacket/blazer. Pant suits are an option for any gender, and as long as it doesn't look like you're going to prom right after the interview, you will look fine.
For recruiting events/socials, depending on your audience, business casual is probably a safe bet. Dress down a bit if you're doing events with only grad students. A business-casual interview option that works in interview/social environments are sweater vests and dress pants/skirt.