Let’s figure out how to create a cold wallet and truly protect your crypto assets. I’ve been using this setup for several years, and I can say that it really works.

For beginners who are just getting started, if the amount is small, you can simply use reputable hot wallets such as MetaMask or Trust Wallet. But if you take security seriously and want to protect your mnemonic phrases from being connected to the internet, then a cold wallet is what you need. And you know what? You can create a cold wallet literally from an old iPhone lying around at home.

Here’s what you’ll need: one old iPhone that you no longer use. First, reset it to factory settings. Then delete unnecessary apps (you can keep system apps), connect to WiFi, and download imToken or AirGap Vault—these are apps that support offline signing.

Next—and this is an important point—turn off internet on that phone. Delete all saved WiFi passwords, open the app, and for every permission request, answer “no.” Now you can import your mnemonic phrase or create a new wallet. If you create a new one, be sure to write the phrase down on paper and hide it—never store it in the cloud or on internet-connected devices.

If all you need is to store coins, you can stop here. Transfer your assets to the address of this wallet and monitor the balance via a blockchain browser from another phone. But if you need to make transactions, then the process is a bit more complicated.

For transactions, select the correct address in imToken, open the account details, and tap “Connect another wallet.” You will see a QR code. On the second phone, which is connected to the internet, open MetaMask, add the hardware wallet via the QR code, and scan that code. Choose the address you need.

Now you have two phones: one that’s offline (the cold wallet) and one that’s connected (the observer). When it’s time to send a transaction, open the observer wallet in MetaMask, tap send, and a QR code for the signature request will appear. Take the offline phone, open offline signing, verify the amount and address, and if everything is correct, sign. A new QR code will appear on the offline phone. Go back to the connected phone, scan this code, and the transaction will be sent.

That’s the entire process for creating a cold wallet. I recommend using an iPhone rather than Android, purely for security reasons. As for the app choice, I use imToken for demonstration, but AirGap Vault is also a good option.

One important warning: a cold wallet protects your private keys from the internet, but that doesn’t mean absolute security. If you sign a transaction yourself to the address of a malicious project, the funds will be lost. Therefore, always—literally always—carefully check the address and amount before signing. This is the final and most important line of defense—your attentiveness.