Just be original and have faith on yourself
THUMBNAILS are important and so are catchy titles
A good thumbnail Plus a good title should be used , it should be like that makes audience curious about it
Make good quality videos that's it , quality attracts more ,even I've YouTube channel and this is all I've learned that quality is the key point whether its video ,audio or content.
Don't fake anything, stay original, that is what Audience loves.
Be consistent with the content you post. Like your content, if you don't like what you're posting, you can't be sure whether your audience would enjoy it. Good luck!