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Explain what you were doing on the video. It makes it more human, I think.

I could write in the blog about the changes I've made during that day.

Oh, yeah! That could be a very good way of improving it.

In my personal taste, I prefer posts which are just not only YouTube videos, as I could just go there and subscribe if I like them. But I remark, that it is just my personal taste. Many YouTubers are doing it like you and they are doing well, on the payout side :)

I really think that adding some explanation to the post will do it much more better.