I'm with Pete I use them off of my main line. Either like you I tie my leader with an improved cinch knot at the
swivel with 3-4' going down as my main line and 7-12" as my teaser end. If I add it to my leader afterward same thing 7-12" tied on the swivel where my mainline is tied. I think the trick to keeping it from wrapping and fouling is not to have the teaser part too long, shorter is better. How long are you making them?
Thought about using a dropper but never really found I needed to.