Creating our vault

We will be creating a brand new offline bitcoin wallet with its first access point being the ColdCard itself.

After completing this guide, we will technically be able to sign transactions to spend from our vault, but only after completing the next section, will we have the ability to view our balance and create transactions to sign.

Table of contents

1. You will need
2. Reference material
3. Instructions
   1. Initial setup
   2. Creating seed words
   3. Recording the identity fingerprint
   4. Testing our temporary backup
4. To recap

You will need

• A ColdCard (MK3 or later)
• One or more 6 sided dice
• Scrap paper and pen

Reference material

This section will lean heavily on the setup documentation from the official ColdCard website. The site provides a few similar guides which I will link here for convenience:

• The ultra-quick guide: https://coldcard.com/docs/ultra-quick
• The official quick guide: https://coldcard.com/docs/quick
• The middle-ground guide: https://coldcard.com/docs/middle-ground
• The paranoid guide: https://coldcard.com/docs/paranoid

Have a skim of them, you can even take the time to familiarise yourself with the ColdCard’s features before beginning, however keep in mind that we will be creating a brand new empty wallet in this guide, so avoid sending any money to the device just yet.

Instructions

Initial setup

Using any of the guides above to check the device for tampering and ensure it is genuine. If you are following the paranoid guide, you should also update the firmware at this point. Finally, set up and jot down your access pin and anti-phishing words on a piece of scrap paper.

Do not use a digital device as an alternative to a blank sheet of paper and write on a hard surface that will not leave an imprint of what you are writing. We will be destroying the scrap paper at the end of this guide to properly secure our vault.

Creating seed words

To set up our seed words, select New Wallet. Once we are presented with 24 words, press the (4) key to add dice rolls and enter at least 25 dice rolls before pressing the OK (✔) button.

Don’t trust, verify

If you are able, you should follow the verify guide to prove that your device is fair. You can then repeat the same steps providing 99 or more dice rolls to produce 256 bits of entropy for your new wallet.

Once complete, the ColdCard will present you 24 words and ask you to write them down. Write this onto your scrap paper and underline the last word (we will refer to this last word later in this guide).

The device will then ask you to prove that you wrote the words down by having you re-confirm the words in a random order. Once you have completed the test, you will have a new empty wallet.

We do not recommend setting up a passphrase for a vault. The passphrase would become a secret that must be shared between each of our access points and will complicate our set up unnecessarily.

Recording the identity fingerprint

Your coldcard now has an identity fingerprint. This is a short code that can be used for comparison when restoring your wallet later, to confirm that you have restored it correctly. You can find this fingerprint by navigating the menus: Advanced > View Identity. Write down this fingerprint code as it will be useful later on in this guide.

Testing our temporary backup

The final step is to reset and restore our wallet. We haven’t sent any bitcoin to our wallet yet, so this is the perfect opportunity to familiarise ourselves with the process. To reset the device, use the navigate the menu: Danger Zone > Seed Functions > Destroy Seed. You will need to read and follow any instructions or warnings presented.

To restore our wallet, we navigate: Import Existing > 24 words and enter our 24 words. To confirm that everything went correctly, visit: Advanced > View Identity and verify that the fingerprint is the same.

To recap

1. Check the device for tampering
2. Update the firmware (optional)
3. Setup our access pin
4. Record our pin and anti-phishing words on scrap paper
5. Select New Wallet
6. Press 4 and add at least 10 dice rolls
7. Write down the 24 word mnemonic onto scrap paper
8. Underline the last word
9. Complete the verification test
10. Select Advanced > View Identity
11. Write your fingerprint onto scrap paper
12. Reset the device: Danger Zone > Seed Functions > Destroy Seed
13. Restore your device: Import Existing > 24 words