For your chess kitty party, why not make it a semi-black tie affair? Have guests dress up in their black and white bests. Gentlemen can wear nice black pants and a white button down shirt and ladies can wear black and/or white cocktail dresses. If you don’t want your kitty party to be really fancy, let guests know that it is preferred that they wear all black or all white (you can even designate men to wear all black and women to wear all white - or vice versa).