It's insane that one has to go through this to be somewhat safe.
Keep the seed phrase safe. Use actual dice to generate it. Put a chunk of it into your wallet, a chunk into your password manager, a chunk in your attic or in a book, etc. Never type it into an internet connected computer.
Oh and, never tell anyone about how much crypto you have.
This is reasonably safe, and reasonably within the capabilities of a non cryptography nerd.