I leave a tag of backing, about 6", with a loop, on the end of my fly line, then make a loop on the remaining backing on the spool. InNterchange lines via loop to loop.

May not be the right way, but it's worked well for me...
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[Bleeeeep!], the cup of ignorance in this thread overfloweth . . . Salmo g
Truth be told, I've always been a fan of the Beavs. -Dan S.