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Lesson 4 · Operational Security

Self-custody security checklist

Use this checklist to review wallet setup, backups, transaction verification, privacy, recovery and emergency planning.

Practical checklistReview regularlySecurity before convenience

Security overview

A secure wallet is a complete system

Self-custody security depends on more than one device or one backup. It includes how the wallet is created, how recovery information is stored and how transactions are reviewed.

A strong setup should protect against theft, accidental loss, device failure, phishing, physical damage and user error.

The most secure system is one you understand and can recover calmly under pressure.

Core principle

Security should reduce single points of failure without making recovery too complicated.

Before setup

Prepare before creating the wallet

Choose a trusted wallet

Use established wallet software or hardware from a verified official source.

Use a clean device

Update the operating system, remove suspicious software and avoid public or shared computers.

Understand the recovery process

Know how the wallet can be restored before storing a meaningful amount of bitcoin.

Plan secure backup storage

Choose where recovery information will be kept before creating the wallet.

Wallet setup checklist

Create the wallet securely

1

Download wallet software only from the official source

2

Verify the device or software is new and not preconfigured

3

Generate the wallet yourself

4

Record the recovery phrase accurately and in the correct order

5

Keep the recovery phrase offline

6

Set a strong wallet or device PIN

7

Avoid reusing passwords or PINs

8

Test the recovery backup before transferring significant funds

9

Send a small test transaction first

Stop immediately

Never use a wallet that arrives with a seed phrase already created.

Transaction checklist

Verify before approving

Verify the receiving address

Check the address on a trusted device before sharing it or sending bitcoin to it.

Check the destination address

Compare the full destination address carefully before approving a payment.

Review the amount

Confirm the amount shown is exactly what you intend to send.

Review the fee

Make sure the transaction fee is reasonable for the urgency of the payment.

Use a small test payment

For a new address or large transfer, consider sending a small amount first.

Pause when details differ

Do not approve anything when the wallet device and computer show different information.

Take your time

Bitcoin transactions are generally irreversible. A short pause to verify the details is worth more than rushing.

Backup checklist

Protect against device failure and loss

Keep at least one reliable backup

The backup must be complete, readable and able to restore the wallet.

Separate wallet and backup

Avoid storing the signing device and its only recovery backup in the same location.

Protect against physical damage

Consider fire, water, humidity, theft and accidental disposal.

Do not store seed words digitally

Avoid photos, cloud documents, email, messaging apps and ordinary text files.

Test recovery

Confirm the backup works before relying on the wallet for significant savings.

Plan for inheritance

Ensure the intended beneficiary can recover the wallet without exposing the seed phrase now.

Reliable backup

Complete, readable, private, durable and tested.

Weak backup

Unverified, photographed, incomplete or stored beside the wallet device.

Privacy checklist

Reduce unnecessary information sharing

Use your own Bitcoin node

A wallet connected to your own node reduces the need to reveal addresses and balances to third-party servers.

Avoid address reuse

Use a new receiving address for each payment when the wallet supports it.

Limit personal information

Avoid linking wallet addresses publicly to your identity unless necessary.

Use trusted networks

Avoid managing important wallets over unknown public Wi-Fi networks.

Phone

Use trusted apps and keep the device updated.

Computer

Avoid untrusted software and suspicious downloads.

Node

Verify balances and transactions using your own node.

Ongoing maintenance

Review the setup over time

Monthly

Confirm the wallet application still opens normally

Check for official software or firmware updates

Review recent transactions

Confirm your node is syncing correctly

Every 6–12 months

Inspect physical recovery backups

Confirm backup locations remain secure

Review emergency and inheritance instructions

Check that replacement hardware remains available

After a major change

Retest recovery after changing wallet setup

Update instructions after moving backup locations

Confirm all signers understand a multisig change

Move funds if a seed phrase may have been exposed

Emergency response

Know what to do before a problem occurs

Seed phrase may be exposed

Create a new wallet with a new recovery phrase and move the funds as soon as it is safe.

Hardware wallet is lost

Restore the wallet using the recovery phrase on a compatible trusted device.

Wallet device still works but the backup is lost

Create a new wallet and transfer funds before the device fails.

You approved a suspicious transaction

Review the transaction immediately and move remaining funds to a new secure wallet if necessary.

Computer or phone is compromised

Stop using the affected device for wallet activity until it has been cleaned or replaced.

A custodial service blocks withdrawals

Follow the service process, preserve records and avoid sending additional funds.

Final review

My self-custody setup is ready when

I control the private keys

My recovery phrase was generated by me

My recovery phrase is stored offline

I have verified every recovery word

I have tested the recovery process

I understand how to check transaction details

I know how to recover after device loss

My wallet software came from an official source

I use a setup I can explain and operate

I have considered privacy and inheritance

Never rush into a more advanced setup until you can recover and operate your current setup confidently.