To create Youtube post follow given below steps:
Step-1 : Go to Posts -> Add New
Step-2 : Put title for your post
Step-3 : Put content for your post into text editor.
Step-4 : After that go to Meta Options -> Post Meta. In that please select left sidebar from Sidebar Configuration drop-down.
Step-5 : Select your sidebar widget which you want to show in your post from Left Sidebar drop-down.
Step-6 : Publish your post to make it live.