As others have said, it is the total look that counts! I wear off-white for Highland dancing with flashes of the same tartan as my kilt. That shows off the laces of the dancing gillies . Otherwise I often wear coloured. I pick colours that match or complement the colours in the Kilt. For dress, I use diced hose in red and green (colours in my dress kilt). As always it is a matter of making the total picture look good.