This is your signature. Then verify the signature:
verify_message "My Message" QWC1LxPvCVibmBUAaJu1hm8xk35UjJqYvTA4AisTSerheZ53Yse3SwAg8U7WkPcDAxZH1QpqDVxBcKvDUmMUuRJuAEZa9HzZm9 SigV1fYJ8t1rf4UkNATJFK7fxmJAcg9GCBGG9dXrr7bs4KZNBjnFgNJ33256MFRX7AG2q1Kdi8XQDruMkZbiNwXwAsLb9
Valid signature from QWC1LxPvCVibmBUAaJu1hm8xk35UjJqYvTA4AisTSerheZ53Yse3SwAg8U7WkPcDAxZH1QpqDVxBcKvDUmMUuRJuAEZa9HzZm9
If you sign this text yourself you will probably get a different signature than me. This is because the signing is not deterministic. Nevertheless, you should be able to verify my signature without problems.
Sign & Verify using the GUI Wallet
Create a new wallet from the example seed above
Navigate to File > Sign message Write My Message in the the message field at the top.
Copy the generated "Signature" into the verification field (Verify message) or navigate to File > "Verify signed message" Copy the message into the verification "message" field. Paste the Qwertycoin address in the "Address" field Your Message will be verified.