Hey there, well I can offer a few tips, I grew to 47 subscribers in a couple of months, which is a normal rate, and all I did was show viewers how one of my realistic paintings is done, from start to finish, I then started getting into some tutorials, I did a couple of videos where I discuss oil painting related stuff, I did some advice videos, and just kept talking to the audience as if they were really standing in front of me, I keep the unnecessary rubbish out of my videos and get straight to the point, but still have an intro, I recently started sharing someoneΓÇÖs merchandise store as well, so all I can say is just make some great looking videos (obviously), but also find some gaps within the niche that need filling, and then fill it in whatever way you need to, break down a painting into a few videos (something I plan on doing this coming week), rather than just do it all in one go, or even do quick tutorials showing how certain parts of painting are done, but most importantly focus on content making while ignoring the numbers and just have fun doing it.
ItΓÇÖs worked for me so far, but apply your own style to what you do, and remember this is a loooooong journey so patience is a must. Good luck with your channel.