Happy to see you realize that.
I can't really give you any tips since I am really new to this and I am simply posting content without anything (no promotion,no other platforms, nothing)
And there is so much different factors that come into play in this social media game that I can't give tailored advice.

The number one thing though I'd say is (consistency + content) if you have both I don't see how your channel could not grow.

First simply share stuff you like, then let it ride for a while before even considering various strategies. But we all start from a different stage at the end.

I can't help you out more past that point since even my following base is small and I have zero intention to focus on promoting anything to make it grow before quite some time. I first figure out a pace at which I am happy posting. That's just me. Find yours and enjoy :)