Where to document

Everyone always says to document the abuse. Easier said than done when it’s constant. How can I document or even recall everything happening 24/7? That said, I try to take videos but he always grabs my phone and deletes them. I’ve tried using my notes app, he deleted the notes. I’ve now tried sending via email to a separate email I made, he found it on my phone and deleted them. Sometimes I’ve even forgotten where exactly I tried to secretly document xyz because I’m always having to change it up.

Is there anyway to document when your abuser is aware you’re documenting and actively tries to delete it? Am I missing some sort of secret trick? And what exactly are you writing down that is quick to write? I don’t have time to write novels every single day, especially when he’s right there watching me.