I store it in paperless. I save it there for the longterm but also to have it ready when needed. If I guess I don’t have internet. I save it on my phone as well.

I print hard copies because (a) I’m a dinosaur (b) it’s easier than fumbling with a phone

pdf in my nextcloud

I put them in my password safe

Save them as PDFs and store them in your cloud storage or choice or a syncing tool like Syncthing. A basic folder structure can help keep things organised.

No need for anything complicated, for essential documents best to keep its impel and limit the scope of failure.

Like most others I use paperless-ngx.

On top of that, I use syncthing to sync the paperless files to my mobile phone. You can set storage path for each file in paperless; I have one for important files like tickets. Then I have them even without internet access 🙂👍

I also use email and company apps (flights, …) … 🫣 For movies I also use “note to self” in signal to quickly store and find them…