#bitcoin cold storage levels. More security adds more complexity. Most people are fine with level 2 or 3:

1. Open Source hardware wallet with paper backup

2. Open source HWW with steel backup

3. Open source HWW with steel backup and passphrase

4. 2 of 3 Multisig using open source multi-vendor HWW with BSMS file and steel backup spread out in the same country

5. 3 of 5 Multisig connected to your own node using open source multi-vendor HWW with steel backup and BSMS file that are spread out over 5 different countries

6. Same as 5, but with a passphrase on each key