I think you can't if you have a Youtuber account. Try changing it to Director, Guru, etc.
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Are you asking how to convert a Scratch project to a video format that can be uploaded to Youtube? That can be done by using video capture software on you computer. You set up the software to capture a section of your screen, then you run your project.
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Paddle2See, it's _not_ about Scratch, it's about I've got an account on youtube and want to set up a banner saying "subscribe me!" on my videos, like user called machinima did. That's why I've put this here, and not in Scratch category
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