Start by creating a Google Cloud project if you haven't already. This can be done by visiting the Google Cloud Console, clicking on the project dropdown, and selecting "New Project". Give your project a name, set the billing account, and note the Project ID for future steps.

Once your project is set up, navigate to the "APIs & Services" section in the Google Cloud Console. Search for "Pub/Sub API" and enable it. This allows your project to use Google Cloud Pub/Sub services for messaging.

In the Google Cloud Console, go to the Pub/Sub section and create a new topic. Click "Create Topic", provide a unique name for the topic, and set any desired configuration options. This topic will serve as the endpoint for messages you publish.

On your local machine, download and install the Google Cloud SDK from the official Google Cloud website. The SDK provides the `gcloud` command-line tool, which is essential for managing Google Cloud resources and authentication.

Execute `gcloud init` from your terminal or command prompt to authenticate with your Google Account and configure your default settings. Follow the prompts to set the default project and authentication method. This step ensures your local environment can interact with Google Cloud services.

Develop a script in your preferred programming language (e.g., Python) to publish messages to your Pub/Sub topic. Use the Google Cloud Client Libraries for your language. For Python, install the client library with `pip install google-cloud-pubsub` and use the following template:

```python
from google.cloud import pubsub_v1

project_id = "your-project-id"
topic_id = "your-topic-id"

publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path(project_id, topic_id)

def publish_message(data):
# Data must be a bytestring
data = data.encode("utf-8")
future = publisher.publish(topic_path, data)
print(f"Published message ID: {future.result()}")

# Example usage
publish_message("Hello, World!")
```

Replace `your-project-id` and `your-topic-id` with your actual project and topic IDs.

Run your script to publish messages to the Pub/Sub topic. Verify the successful delivery of messages by subscribing to the topic using the Google Cloud Console or `gcloud` command-line tool. You can create a subscription via the console and pull messages to verify they are being received correctly.

By following these steps, you can move data from your local environment to Google Cloud Pub/Sub without using any third-party connectors or integrations.