Easy. Go look at your original birth certificate, and look where it says “sex” on it. If it says male, buy stuff us guys wear. If it says female, go buy girl clothes (dresses preferably, women are awesome when they dress in feminine attire). If your birth certificate has been rewritten to conform with leftist ideology, just look down below. If you have an appendage...by boy clothes, if you don’t, or there’s a scar where it used to be...buy girl clothes. Just two cents from an accused bigot, transphobe, fascist, etc...etc...
My answer would be “black pants and a white shirt,” unless your employer’s uniform calls for tan or navy blue pants.