Complex sentence: He first appeared in Big Time Audition, where he tried teaching Big Time Rush how to dance; however, they ended up stressing him out, after which he "said a bunch of bad words that started with'X'" and quit.
Split into simpler sentences: He first appeared in Big Time Audition, where he tried teaching Big Time Rush how to dance. However, they ended up stressing him out, after which he "said a bunch of bad words that started with'X'" and quit.