We have a young man, whose father is a member here, that wanted to be able to fish with his Dad. Tying on the flies was, at that time, beyond his capabilities. We devised this:, and this:
Or you might simply want to pre-line the tippet to the fly, and make a loop in the end of the tippet, and a loop in the end of the leader, you can do a "hand shake" connection on the fishing stream. No tools needed.