Get some Maxima Chameleon as equal to the diameter of the store-bought leader's butt section you usually use as possible. Nail knot it to the fly line (using a nail knot tool, I can do Maxima .022 and I'd bet I could do thicker). Make this butt section about 6" long, including surgeon's loop (a perfection loop is a total PITA with Chameleon).
Attach store-bought leader with hand-shake connection.
Go fishing.