Complex sentence: The Free Festival was set up by Alex Petty of Laughing Horse, who has organised free venues at the Edinburgh Fringe since 2004, originally in a partnership with The Free Fringe founded by Peter Buckley Hill, splitting away from that organisation in 2006.
Split into simpler sentences: The Free Festival was set up by Alex Petty of Laughing Horse, who has organised free venues at the Edinburgh Festival Fringe since 2004. It was originally in a partnership with The Free Fringe founded by Peter Buckley Hill but split away from that organisation in 2006.