About the production of personal cold wallet
As a crypto enthusiast, you should always remember "not your keys, not your coins" and it is important to know how to make a cold wallet yourself.
1. First prepare a formatted old mobile phone, Apple mobile phone is recommended.
2. Download an open source software wallet from the official address. (If you only want to store Bitcoin, I recommend BitTorch Wallet. If you have multiple currency needs, you can choose Trust, which is an open source wallet acquired by Binance. I have always used Huobi Wallet, a non-open source wallet, and think this This wallet is backed by Huobi and has the credit endorsement of Huobi. There should be no backdoors. The fact is that it was exposed some time ago that the Huobi wallet opener secretly left a backdoor, so non-open source wallets must be cautious.
3. Generate mnemonics offline. (The key to a cold wallet is that the private key/mnemonic phrase does not touch the Internet. The purpose of choosing an open source wallet to generate the mnemonic phrase is to ensure true randomness. If it is a non-open source wallet, there may be pseudo-randomness that limits the mnemonic phrase library to a certain small range. It can be cracked through brute force, and there are security risks. If you can't even trust the mnemonic phrase generated by the open source wallet, you can manually generate a random mnemonic phrase by rolling dice. For the specific implementation method, please refer to my other articles for detailed steps.
4. Back up and verify mnemonic phrases. (Make a note of the mnemonic phrase, delete the wallet, re-enter the mnemonic phrase, and verify that the addresses are consistent. As for the storage of the mnemonic phrase, I will write an article specifically to introduce it.
5. To monitor the wallet, use a commonly used mobile phone to download a hot wallet and enter the wallet address. TP wallet, imtoken, SafePal, etc. are recommended.
6. Cold wallet transfer. (For example, Bitether Wallet supports the production of cold wallets. Two mobile phones download Bitether wallets respectively. The hot wallet performs transfer operations. The cold wallet uses a QR code to sign and authorize. For open source wallets that do not support cold wallet production, transfer money out. , temporarily connect to the Internet, and clear the wallet once. This is suitable for currency hoarders and people who do not often operate. Frequently traded assets can be placed in hardware wallets, or dispersed on leading exchanges such as Binance and Oui)