Maaan first of all thank you to be soooo kind all the time and follow my weekly trick and always have a good word 
I have to say that I am a classic case of “i dont know what I am doing”, I know zero about light and photography but generally I follow couple rules.
Always film with the light behind the camera and when is light outside, i do not use artificial lights, i put my phone with behind a window and no lights behind me, in this way I use the natural light outside that come from the window, I see it got much better result than use artificial lights.
You need a good phone or recording source, probably this is the most important, I invested not even a year ago on a Samsung S23 Ultra which I will pay until I will go to retirement, but it worth it as the video/photo quality is just insane, i record everything 4k and 60fps and then Instagram will provide to destroy a bit the quality 
Than I use a dark background and dark clothes, this is the most important thing also I use neon yellow strings that really pop up with me dressed full black and with the “dark” background, if you would like you can use the black background like many people does, I choose something different to create something “recognisable” as everyone use the dark background.
After recording, I do some colour correction in my case i remove a bit of light and do some more dark shadows so the string pop even more as everything become a little bit darker, than put some contrast and I put very down the warmth of the video so has that blueish tint (which is just my preference, I like how it looks), I usually mess a bit aroind with the settings but also the colour correction I try to keep it similar to make it recognisable to people. Ah, I use Inshot to edit the combo so nothing hard to use!
This is pretty much all I do, have a good sourcing record and stay with the light in front of you is what I try to do to have a clean video, than it happened thousand times that I came out blurried out of focus, or I didnt push the record button or I just play out of frame, all things that make you scream against God but in general is quite fun to do videos and is a satisfaction when its done! 
