www.youtube.com/watch?v=2csupFzN_qA
How To Change A YouTube Channel Name - 2014 -- David Walsh shows you how to change a YouTube Channel Name and Username on a YouTube Channel.
support.google.com/youtube/answer/3046356
With YouTube channels connected to Google+ pages, you can manage up to 200 channels from one Google Account. Learn how to connect your YouTube channels to a Google+ page.