Hair razor, which is what I usually use:
Thinning shears (I found these harder to use but it’s easier to thin thicker hair with them!):
One tutorial, but a bit advanced because she’s using normal scissors. You can copy this with a hair razor, though I think
If you search “visual kei hairstyle” you should get more too. I would also try looking for videos for scene hair, becuase it is similarly heavily layered.
It’s really surprising how much you end up cutting off to make the layers! You have to be pretty bold with it, but it’s hard to mess up too bad with the hair razor imo
And yeah, I’m seconding finding someone who does these kinds of hairstyles if you ever go to a salon. I’ve gone to Ulta, Fantastic Sams, Toni&Guy, and a few other lower end ones and nearly every single one could not layer my hair properly. No one here knows alternative hair at all (and have actually told me some styles were impossible lol) so I gave up going to salons unless I actually go into downtown. It seems hard to find in TX aside from major cities.