Knickers on top, this also makes it possible for the stockings and suspenders to be kept on for further bedroom activity when other clothing has been discarded. Apparently. Cough. Anything other than recreational stocking wear and you need to get a proper 6 strap suspender belt from somewhere like What Katy Did or Stockings HQ.
I hate wearing tights so it's stockings or hold ups for me whenever a dress or skirt is worn. Knickers on top and as MsArseBiscuit says, a good 6 strap suspender belt makes for a much better wearing experience.