You say "so the fabric doesn't ripple". Are you using a hopping foot or a foot made for the frame? You can't use regular feet on the frame. If you are using a hopping foot, the foot should just hover over the quilt, maybe a dime thicknesss. The height is usually adjustable if you check your foot - it should not cause ripples.
As far as attatching leaders I don't know your frame. Some put their leaders on velcro -sticky on the roller and sew-on on the leader. I have also heard about taping the leaders on the rollers using Scotch brand (only that brand) duct tape. Use what ever will take up less space on the roll so you don't lose quilting space. Good luck, it will work and be fun. Practice, practice is the best way to learn.
There are several yahoo groups if you search for frame quilting, and I'm sure there is one for Juki.