I have found most faire security don't care if the handle is attached to a blade, shoehorn or bottle opener, they will want to make it so all their staff know it has been inspected. This often includes peace tying something that really doesn't need to be. Having worked security at various events I appreciate the clue but also see the ridiculousness this sometimes breeds.

Because of this there is no need to make the tying fit in or be discrete. I often tie my blades with fluorescent colored plastic wire ties. In the case of a small blade with no easy loops to tie onto, I usually tie one around the handle, 1 around the sheath and two on the sides to connect those two ties. In the case of a sgian dhu that will be in your hose make sure that the one on the sheath does not catch on your hose.