Source: Talk Li Talk Outside
For newcomers, if the fund size is not very large, as long as you can improve your own awareness of safe use, you can directly use the exchange or hot wallet (it is best to choose those with relatively high reputation and good reputation, such as MetaMask, Trust Wallet, OKX Web3 wallet, etc.).
But if you really want to use a cold wallet (also called an offline wallet or hardware wallet) to improve the security of your seed phrase/assets, it's also very simple, just use an old Apple phone to create a cold wallet.
Preparation: An old Apple phone you don't use
Step 1: Reset the old Apple phone and restore the factory settings.
Step 2: Delete unnecessary built-in apps on the Apple phone (you don't need to delete the system apps, and if you have obsessive-compulsive disorder, you can delete some), then connect the phone to WiFi and download an imToken wallet (you can also use other wallets that support offline signing, such as AirGap Vault).
Step 3: Disconnect the Apple phone from the internet and delete the WiFi password, then open the imToken app (if it prompts you to allow XX permissions, click "Don't Allow" and also don't allow it to connect to the network).
Step 4: Import your seed phrase or create a new wallet (if you are afraid of the phone being lost or damaged and unable to boot, you must keep the seed phrase of the new wallet safe, such as writing it down on paper and hiding it, but do not store it on a computer/cloud drive that is connected to the internet).
If you are just hoarding coins, you can basically stop here. You only need to transfer your coins to the address of this wallet from time to time. Then you can use the blockchain browser or the observation address function of other online wallets to check the balance.
If you also need to use the cold wallet to make transfer transactions, then continue reading:
Step 5: In imToken, select the corresponding wallet address, such as the Default 1 address of the Ethereum chain (this is just an example), then open the account details page and click "Connect Other Wallet" to see a QR code.
Step 6: Then open the wallet (such as Metamask) on another connected phone, click "Add Account or Hardware Wallet", then "Add Hardware Wallet", and then click "QR-based" to scan the QR code and select the Default 1 address of your cold wallet.
At this point, the creation of the cold wallet is complete. The phone that is not connected to the internet is your cold wallet, and the connected phone that has added the cold wallet address as an observation wallet can assist in the transfer operation.
So how do you transfer the assets from the cold wallet? Continue reading:
Step 7: Open the observation wallet (the cold wallet address you just paired and added) in your connected phone's MetaMask. For example, if you want to send an ETH transfer, just click the "Send" button. Then you will see a request to obtain an offline signature QR code.
Step 8: Open your offline phone (the cold wallet you just set up), click the "Offline Signature" button on the wallet address page, check the amount and other information, and then click "Send" if everything is correct. Then you will see another QR code.
Step 9: Go back to your connected phone (MetaMask), click the "Get Signature" button, then scan the offline signature QR code from the previous step, and finally click "Send Transaction". At this point, the corresponding assets in your cold wallet will be transferred (after the transaction is completed, you can check the transaction status and progress in MetaMask or on the blockchain explorer).
The above are all the steps. Congratulations, you now have your own cold wallet.
I would like to remind you again that the imToken mentioned above is just for demonstration. It is a wallet developed by a Chinese team, and the user experience may be more familiar with the usage habits of Chinese people. And because it is used in an offline state, the security is basically not a problem, and imToken cannot directly steal your coins in an offline state, but I don't know about the online use (Chinese people don't cheat Chinese people).
Alternatively, you can choose other wallets that support offline signing, such as AirGap Vault, to create a mobile cold wallet (you can search and learn more about this on your own).
For mobile hot wallets, the three I use the most frequently are Trust, MetaMask and OKX Web3 Wallet. For cold wallets, I mainly use Trust (I don't have any transfer transaction requirements for cold wallets). Trust is a wallet under Binance (it was acquired by Binance in 2018).
Warm Reminder: It is recommended to use an Apple phone to create a mobile cold wallet, and it is not recommended to use an Android phone, which is based on security considerations, and there is no more reason for this!
Security Tip: The cold wallet (or you can also call it an offline wallet) only solves the problem of the seed phrase/private key not being connected to the internet, but it does not mean that the funds in your wallet are absolutely safe. This still needs to be considered based on your personal risk awareness. For example, if you authorize the cold wallet to transfer 20,000 USDT to the address of a scam project, once this authorization transaction is signed by the offline wallet, the 20,000 USDT will be completely transferred away and you will not be able to get it back. In the end, when signing, you must carefully check the transaction details, verify the amount and address safety, so as to truly ensure asset security.
