What is your position on patterned tights? Can they be office-appropriate (on a young professional) or are they best reserved for casual settings?
In general, colourful patterned tights don't mesh with day-to-day office fashion and should be limited to cartoons and magazine editorials. In a work environment, you should be seeking appropriate eye contact with your co-workers, not trying to get them to notice your crazy legs.
And before you dismiss me as too strict, know that I make exceptions for monochromatic patterns: ribbing, argyle and dot motifs on all-black tights whisper rather than scream. Tights that convey pattern by varying the denier (or thickness) of the weave, combining sheer and opaque, can be both understated and striking. (Conversely, graphic patterns such as rosettes or Pippi Longstocking stripes are a work-wardrobe strike-out.)
Hosiery in solid dark hues such as midnight blue, charcoal grey or even a deep plum work well. But in this case – really, in all cases – black is best. Above all, remember that statement legwear demands simplicity elsewhere in your ensemble and this is especially important when dressing for the office.