If your channel has more than one hundred subscribers, is in good standing, and you've set up SMS verification for your YouTube account, you can apply for YouTube Live access from your Account Features page. Access to the feature will be granted gradually.
If you don't see the Enable button yet, keep checking back. We're rolling out the feature incrementally in order to ensure a great experience for everyone. Just make sure your account is in good standing and that you remain an active uploader who respects YouTube’s community guidelines.
Once your channel is enabled for live streaming, you’ll see a "Live Events" option in your Video Manager.