The first step to creating a wallet is creating the wallet backup. The reason Bitcoin wallets do this is to make absolutely sure that you created the backup before adding money to the Bitcoin wallet.
Select “New Wallet”.
Get a pen and the piece of paper that has been provided.
Write down the 24 words that are displayed on the Coldcard in their correct order - this is your private key.
Take your time and write them down correctly.
Make sure that the words are easily readable and in the correct order.
Make sure the number in front of each word corresponds with what is displayed on the device.
Triple check to make sure.
Triple check to make sure.
Triple check to make sure.
Find a secure way to store it.
Get creative!
You can do two backups and store them in different places.
You can store your backup on metal, like this one.
If Coldcard or Wasabi wallet suddenly go out of business and they remove their device and application respectively, having your backup will allow you to still have access to your funds.
12. Complete the test to confirm that you have correctly written down the words by pressing on the number that corresponds to the word that is asked of you.
This is an advanced feature that requires you to write down and safe-keep an additional set of 12 words.
You will need an additional microSD card in order to create an ecrypted backup of your 24-word seed phrase, as well as a pen and paper.
Make sure that your Coldcard is unlocked with your PIN;
Insert the new microSD card into your Coldcard;
In your Coldcard go to "Advanced" > "Backup" > "Backup System";
Write down the 12 words in the order in which they are displayed on a piece of paper.
These words are unrelated to your 24-word backup.
In your Coldcard, go to "Advanced" > "Backup" > "Verify Backup".
This is useful for verifying that the backup file on the microSD card was not damaged or written incorrectly.
You must have at your disposition either a new Coldcard or one with no wallet generated (the Backup has been wiped from the device).
In your Coldcard, go to "Advanced" > "Backup" > "Restore from backup".
You will still need your passphrase to access your funds!
The Coldcard uses a random number generator for creating your Bitcoin backup. You can avoid using this if you are wary that it might be compromised or if you wish to input your own source of entropy by rolling a six-sided dice.
Roll your dice 100 times in order to achieve 256 bits of entropy.
Before we attempt the dice rolls in their entirety, we will make sure that the Coldcard isn't duping us into believing that the entropy that we provided is legitimate and they are somehow providing us with a random-looking number that isn't actually random.
Using a pen and paper, note down the results of 6 dice rolls
In the main menu, select 'Import Existing'
Select 'Dice Rolls'
Using the Coldcard's keypad, enter the results you obtained by pressing on the corresponding numbers (1 to 6)
The Coldcard will produce 24 words, write them down
Open the Terminal or Shell of your computer to input a command line
Enter one of the the following commands :
Replace '123456' by the dice roll numbers you obtained
Verify that the hash value output matches that on the Coldcard device screen.
Now we want to verify that the hash value really generates the same 24 words.
Save the script found here: https://coldcardwallet.com/docs/rolls.py
In your Terminal, change the directory to where the above file is saved
Run the following command, using the same dice rolls used for your test by replacing the '123456':
Verify that the 24 words output in your Terminal matches those on your Coldcard!
If they match, then you are good to go with the complete dice roll process.
Using a pen and paper, note down the results of 100 dice rolls
In the main menu, select 'Import Existing'
Select 'Dice Rolls'
Using the Coldcard's keypad, enter the results you obtained by pressing on the corresponding numbers (1 to 6)
The Coldcard will produce 24 words, write them down
You now have your 24 word backup generated using your own source of entropy!