Before moving data to Google Pub/Sub, ensure you understand how your data is being merged. Clearly define the format and structure of the merged data and how it is stored or accessed within your system. This is crucial for extracting the correct data for publishing.

If you haven't already, set up a Google Cloud Project. This involves creating a project in the Google Cloud Console, enabling billing, and setting up the Google Cloud SDK. Ensure that Pub/Sub is enabled for your project by navigating to the API library in the console and enabling the Pub/Sub API.

In the Google Cloud Console, create a new Pub/Sub topic. A topic is a named resource to which messages are sent by publishers. Navigate to the Pub/Sub section, click "Create Topic," and give it a unique name. Note this name as you will need it for the publishing process.

Set up authentication for your application to interact with Google Pub/Sub. This typically involves creating a service account in the Google Cloud Console, downloading the JSON key file, and setting the `GOOGLE_APPLICATION_CREDENTIALS` environment variable to the path of this key file on your server or local machine.

Implement a method to extract the merged data from your system. This could be a script or a function depending on how your system is set up. Ensure the data is in a format that can be serialized into a message format for Pub/Sub, typically JSON or plain text.

Use the Pub/Sub client library for your programming language of choice to publish the extracted data to the topic you created. Initialize the Pub/Sub client, specify the topic, and use the `publish` method to send the data. Ensure you handle any exceptions or errors in the publishing process to maintain data integrity.

Example in Python:
```python
from google.cloud import pubsub_v1

publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path('your-project-id', 'your-topic-name')

data = 'Your merged data' # Ensure this is in bytes
data = data.encode('utf-8')
future = publisher.publish(topic_path, data)
print(f'Published message ID: {future.result()}')
```

After publishing, verify that your messages are being delivered to the topic by subscribing to it. You can create a subscription in the Google Cloud Console and pull messages to ensure they have been received. This step helps in confirming that the entire process is functioning as expected.

By following these steps, you can successfully move data from a merge operation to Google Pub/Sub without relying on third-party connectors or integrations.