In the fast-evolving world of cryptocurrency, securing your digital assets is more important than ever. One of the most effective ways to protect your Ethereum (ETH) and ERC-20 tokens is by using a cold wallet—a wallet that remains completely offline and immune to online threats. This guide walks you through the process of creating an Ethereum or ERC-20 cold wallet using imToken, performing offline transaction signing, and ensuring maximum security without sacrificing usability.
Whether you're a beginner or an experienced crypto user, understanding cold storage, offline signing, and observation wallets can significantly enhance your asset protection strategy.
Why Use a Cold Wallet?
A cold wallet stores your private keys offline, making it nearly impossible for hackers to access your funds remotely. Unlike hot wallets connected to the internet, cold wallets eliminate exposure to phishing, malware, and exchange breaches.
However, since a cold wallet is offline, it cannot directly broadcast transactions. That’s where the concept of an observation wallet comes in—a linked online wallet that monitors your balance and prepares transactions, which must then be signed offline using your cold device.
👉 Discover how secure crypto storage starts with the right tools and practices.
Step-by-Step Guide to Setting Up Your Cold Wallet
Step 1: Prepare Two Devices
You’ll need two smartphones:
- Offline Device: Used exclusively for storing your private keys and signing transactions. This phone should never connect to Wi-Fi, Bluetooth, or any network.
- Online Device: Connected to the internet and used to manage your observation wallet, view balances, and initiate transfers.
Both devices must have the imToken app installed.
🔐 Security Tip: Consider resetting both phones to factory settings before starting to ensure no malicious software is present.
Step 2: Create the Cold Wallet (Offline)
On your offline device, open imToken and create a new Ethereum wallet. Follow the setup instructions carefully.
Once created:
- Write down your recovery phrase on paper and store it securely (e.g., in a fireproof safe).
- Never take a screenshot or store it digitally.
- Confirm that the wallet is created successfully and remains offline.
This wallet will now serve as your cold signing wallet.
Step 3: Import as Observation Wallet (Online)
Now switch to your online device.
- Open imToken.
- Go to Me → Wallet Management → Add Wallet → ETH.
- Select Cold Wallet.
- Use the scanner to scan the public address QR code from your cold wallet.
Note: You’re only importing the public address—not the private key or recovery phrase.
After scanning, you'll see a prompt to generate an "Authorization Signature" QR code.
Step 4: Authorize the Connection Offline
Return to your offline device:
- In imToken, go to Wallet → Scan QR Code (top-right corner).
- Scan the Authorization Signature QR code from the online device.
- Enter your wallet password when prompted.
- Tap Authorize Signature.
The app will generate a new QR code—the signed authorization response.
Step 5: Complete Setup on Online Device
Back on your online device:
- Click Next after generating the initial QR code.
- Tap the Scan box and scan the signed QR code from your offline device.
- Confirm the import.
You’ll now see a message: "Wallet setup successful."
Your observation wallet is ready. It mirrors your cold wallet’s address but cannot spend funds without offline approval.
✅ Your cold wallet setup is now complete.
How to Send ETH or ERC-20 Tokens Using Cold Signing
Since your cold wallet is offline, sending funds requires a two-step process involving transaction preparation and offline signing.
Step 1: Prepare Transaction on Observation Wallet
On your online device:
- Go to Wallet and select your imported cold wallet.
- Choose the asset (e.g., ETH or any ERC-20 token).
- Tap Send.
Enter:
- Recipient address
- Amount
- Gas fee (adjustable based on network congestion)
- Instead of “Send Now,” tap Offline Signature.
- Confirm details and click Next.
- A QR code labeled “Offline Signature Request” appears.
Step 2: Sign Transaction on Cold Wallet
Switch to your offline device:
- Open imToken and go to the same asset in your cold wallet.
- Tap Offline Signature.
- Use the scanner to read the QR code from your online device.
- Enter your wallet password.
- Tap Authorize Signature.
- A new QR code—your signed transaction—appears.
Step 3: Broadcast Transaction Online
Return to your online device:
- Tap Next, then Scan.
- Scan the signed QR code from your offline device.
- The transaction data auto-fills.
- Tap Send Transaction.
The transaction is now broadcasted to the Ethereum network.
Check Me → Notifications for confirmation:
“ETH: 0.04 sent successfully.”
If the transaction fails due to low gas, funds will be returned automatically. You can retry with adjusted fees.
Frequently Asked Questions (FAQ)
Q1: Can I use just one phone for both functions?
No. For true security, the cold wallet must remain completely disconnected from any network. Using one device compromises isolation and increases risk of exposure.
Q2: What happens if I lose my offline device?
As long as you’ve backed up your recovery phrase securely, you can restore the wallet on another device. However, always keep multiple copies of your seed phrase in safe locations.
Q3: Is this method compatible with other tokens besides ETH?
Yes! This process works with all ERC-20 tokens stored in your Ethereum wallet. Just ensure the token is added to your observation wallet for visibility.
Q4: Why can’t I see my balance on the cold wallet?
The cold wallet doesn’t sync with the blockchain unless manually updated via QR codes. Use your observation wallet to monitor balances and transaction history.
Q5: How do I know my transaction was successful?
Your online observation wallet will show real-time updates under Notifications or Transaction History once the block is confirmed on-chain.
Q6: Are there alternatives to imToken for cold storage?
Yes, hardware wallets like Ledger or Trezor offer built-in cold signing, but software-based solutions like imToken provide flexibility for users who prefer mobile-first setups.
Core Keywords for SEO Optimization
- Ethereum cold wallet
- ERC-20 offline signing
- imToken cold wallet setup
- secure crypto storage
- offline transaction signing
- cryptocurrency security
- observation wallet
- blockchain asset protection
These terms reflect high-intent search queries and naturally appear throughout this guide to improve visibility while maintaining readability.
Final Thoughts: Security Meets Practicality
Creating a cold wallet with offline signing may seem complex at first, but it’s one of the most powerful ways to protect your digital wealth. By separating transaction creation from authorization, you gain both security and control over your assets.
While hardware wallets offer convenience, this method using imToken delivers strong protection at no extra cost—ideal for users managing moderate-value holdings directly from their phones.
👉 Secure your crypto journey today—start with a trusted platform that values safety and simplicity.
Remember: In the decentralized world, you are your own bank. Protect your keys, sign wisely, and always verify every step.
With practice, this process becomes second nature—and your peace of mind will be worth every effort.
Ready to take full control of your crypto? Begin setting up your cold storage system now and enjoy truly secure ownership.