I've had great success using (forgive the language) Bastard Amber gels in 1/4 to 1/2 cuts under warm sunlight.
Lay an oversized piece over the opening of a stofen or omnibounce and squish the face of your head into it for a nice snug fit with no light leak. Crumples the heck out of the gel, but who cares. Tape it on for full flash.