If you're somewhat new to crypto currency (as many people are), you probably keep your crypto stored in an online exchange 'wallet' like Coinbase because it's easy and convenient and uses a simple user name and password. These types of all-digital wallets hold your crypto transactions and also manage (own) your crypto private encryption keys and the mnemonic seed phrase (BIP-39 words) used to encrypt transactions and access your funds. You don't own them!
This means that if anything happens to your computer or mobile phone, those seeds can easily be lost forever if you don't have them backed up offline and you may never be able to access your crypto. Even worse, there's a strong chance someone else could gain access via the internet to your online wallet/account if all you have is a weak password and transfer your crypto to a different account - poof, gone! That's not far fetched, it happens all the time. As they say in crypto > “not your keys, not your Bitcoin!”
Screenshot from Andreas Antonopolis video "Bitcoin Q&A: How do I secure my bitcoin?"
If you're looking for an easy way to keep your digital crypto currency safe and offline, you should consider what's called a hardware wallet. Two of the best in class examples would be the Trezor or Ledger Nano. I'm not going to go into detail about how to use a hardware wallet or which model is best, there are plenty of good guides on YouTube that can explain more. However, the term hardware 'wallet' is a little misleading… none of your crypto coins are stored on the hardware wallet device itself, the device is an offline way to store your seed phrase and verify your account and each transaction. If you have more than $100 invested in crypto, you really should have a hardware wallet.
Regardless of which hardware wallet you choose, you should store a physical copy of your seed phrase somewhere offline in a form that cannot easily be damaged or destroyed like paper can- metal is most commonly used for this.
Steel Seed Phrase Backups
You should consider making an indestructible backup of your crypto wallet's mnemonic BIP-39 (Bitcoin Improvement Proposal number 39) seed phrase. A steel seed phrase backup might seem like overkill, but it's actually one of the best options. Steel backups provide protection against fire, flood, and almost any form of accidental damage. Store your seed on a steel wallet backup pretty much protects your seed phrase from everything other than a nuclear catastrophe. Here are some examples.
Some Ready-made Metal Seed Phrase Storage Solutions:
DIY Crypto Steel Backup
You don't have to spend a lot of money to make a steel backup! The cheapest way of making a steel crypto seed backup is to get creative and do it your self. Here is an excellent video by John Chow showing how to make a cheap steel backup of your crypto wallet seed phrase using metal stamps and steel washers from your local hardware store. You can also check out John's website and full instructions here.
This is the method I used to make a two steel backups of my Trezor seed phrase. I store one at home in a safe, and another duplicate steel backup stored at a second location. That way I am covered should anything happen to my house/home.
Below is a picture showing my stamping my steel discs one at a time using a clever little 3D printed jig called a Blockmit made by Crypto Cloaks (you can download the 3D print file and print one yourself if you have a 3D printer). The blockmit jig ensures every disc (steel washer) is held in place and that each letter stamped on the washer is perfectly aligned. It even lets you number each disc/side. Well worth $8.00!
If you have crypto you should use a hardware wallet. If you use a hardware wallet, you should backup your seed phrase onto steel and store offline. It may seem like overkill, but you'll thank me one day.