I'm tired of seeing people using external websites, code, or apps to repeat a youtube video, when it is actually very simple!! Watch this! Youtube has hidden a trick from us which many of us have not known before!
I presume this only works for Adobe Flash based system and Chrome, but I may wrong so go check it yourself!
Enjoy your repeaty video! Have fun!
How to Make a Youtube Videos Repeat Automatically! (2014-NOW,100%still working!)