Running a successful YouTube channel requires a high level of commitment. Most of the successful YouTube bloggers usually do that as a full-time profession. They have a professional team comprising of professional cameramen, video editors and make-up artists.
You haven't shared on what niche or topic you plan to do YouTube blogging. Depending on the niche, the suggestions will vary.
A few common suggestions I can share are:
1. If you notice professional YouTubers, they are quick in the dialogue delivery. The talk rapidly and try to fit as much content as possible in a short time. A long drawn speech with bore your viewer and they might watch that video, but they won't come back to your channel.
2. I am guessing you are not going all-out professional and hiring a team, so the best bet would be to blog on something you are passionate about. That will make sure that you are motivated and authentic in your content delivery.
3. Have patience! It takes many videos and attempts to find the right thing that clicks with your viewers. If you are going to do something like a tutorial, you must be thorough with your content to make sure that your alternatives are low quality and few. But if you are planning to go into a niche with a already high competition, I would recommend taking professional help in form of training and help.
I have myself made YouTube videos and have seen some poor quality videos getting high hits but high-quality videos getting nothing at all. So, YouTube blogging is just like content writing, you have to make sure to keep both the visitors happy as well as YouTube and Google search engine happy.