Google+ options for your channel
To use new and upcoming features that integrate YouTube and Google functionality, first connect your YouTube channel to a Google+ identity which works across YouTube and the rest of Google. You have a few options depending on which name(s) you want to use:
Use only your Google name
You can use your Google name (e.g. from Gmail) on your YouTube channel too. For example, you might have wanted to be “Joey Samson” on YouTube, but the best choice you could find was “jsams587”. Now “Joey Samson” is available, and you can extend your Google name to your YouTube channel.
To do this, just go to your account settings, click Link channel to Google+, and follow the steps. If you don't yet have a Google+ profile, you'll get one with your name.
Use only your YouTube name
Perhaps you have a great brand on YouTube, and you want to use that name across all Google services, for example, as a business account. Or you might not use other Google services. If so, you can replace any other name on the Google Account (e.g. your Gmail name) with your YouTube channel name.
This option is only available if your account doesn't already have a Google+ profile. If this applies to you, then you can go to your account settings, click Link channel to Google+, choose your YouTube name from the list, and follow the steps. You'll get a Google+ profile with your YouTube name.
Use both your Google name and your YouTube name, separately
Maybe you like the way things are set up today. For example, you might use a personal name on Google (e.g., "Jill White" on Gmail), and a brand name on YouTube (e.g., "JW’s Knitting Lessons"). You can keep this setup with the new system by connecting your channel with a Google+ page (instead of a profile).
If you were Jill, you'd keep your regular Google Account with the name “Jill White”, and get a new account for your knitting brand. Your channel would move to that new account, which acts like a subsidiary account that can be accessed from her personal account. Learn more about what happens when you connect your channel to a Google+ page.