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+To use `natools` for message encryption (to destination) and signature (from sender), you would typically follow these steps:
+
+### 1. Generate Key Pairs:
+   - Both the sender and the recipient need to generate their key pairs (public and private keys). You can use the `natools` script to generate keys.
+
+   ```bash
+   # Sender generate keys
+   python3 natools.py privkey -k ~/.zen/game/sender_secret.dunikey -f cred
+   python3 natools.py pubkey -k ~/.zen/game/sender_secret.dunikey -o sender_public_key
+
+   # Recipient generates keys
+   python3 natools.py privkey -k ~/.zen/game/myswarm_secret.dunikey -f cred
+   python3 natools.py pubkey -k ~/.zen/game/myswarm_secret.dunikey -o recipient_public_key
+   ```
+
+### 2. Encrypt the Message:
+   - The sender uses the recipient's public key to encrypt the message.
+
+   ```bash
+   python3 natools.py encrypt -i plaintext.txt -k recipient_public_key -o encrypted_message.bin
+   ```
+
+### 3. Sign the Message:
+   - The sender signs the original message using their private key.
+
+   ```bash
+   python3 natools.py sign -i plaintext.txt -k sender_private_key -o signature.bin
+   ```
+
+### 4. Verify the Signature:
+   - The recipient uses the sender's public key to verify the signature.
+
+   ```bash
+   python3 natools.py verify -i plaintext.txt -p sender_public_key
+   ```
+
+   - The script will output "Signature OK!" if the verification is successful.
+
+### 5. Decrypt the Message:
+   - The recipient uses their private key to decrypt the message.
+
+   ```bash
+   python3 natools.py decrypt -i encrypted_message.bin -k recipient_private_key -o decrypted_message.txt
+   ```
+
+Now you have successfully performed message encryption to the destination and signature from the sender using the `natools` script. Adjust the file paths and content as needed for your specific use case.
+
+Note: Ensure that both sender and recipient securely store their private keys. Public keys can be shared openly. The encrypted message, signature, and decrypted message are intermediate files used for illustration; adjust as needed in your application.