Decoratively tying a sgian dugh into sheath for Faires?

[The Wizard of BC]

Simply skip the Sgain altogether. There is really no function to a Sgain other than the 'look'. Most aren't even sharp or capable of holding an edge. In this case you can't pull or use it anyway so its not a useful tool, just decoration.

When out and around town I do not normally have a Sgain. If I am dressing up, or attending a Scottish themed event, I may put one in my sock for decoration. And my normal decoration is not a Sgain Dubh with a blade, but a Sgain Shoe.