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Play It Cool
About a half-hour before the party starts, lower the thermostat to below 70 degrees, recommends Brooke Scher Mogan, who plans several events a month as vice president at Alison Brod Public Relations. In the nightclub industry, this is called "freezing the box," and it keeps the room from getting fan-yourself-with-a-cocktail-napkin hot when your guests arrive.