Complex sentence: Connor joined the group O2L in 2012 alongside Jc Caylen, Ricky Dillon, Sam Pottorff, Kian Lawley and Trevor Moran and just this year of July 2014, left the group to focus on his YouTube channel.
Split into simpler sentences: Connor joined the group O2L in 2012, alongside Jc Caylen, Ricky Dillon, Sam Pottorff, Kian Lawley, and Trevor Moran. Just this year of July 2014, he left the group to focus on his YouTube channel.