Begin by setting up your development environment. Install Python and the necessary libraries, such as `requests` for HTTP requests and `google-cloud-pubsub` for interacting with Google Pub/Sub.

Sign up for a CoinMarketCap account and generate an API key. This key will be used to authenticate your requests to the CoinMarketCap API. Keep this key secure, as it provides access to your account.

Using Python, write a script to fetch data from CoinMarketCap's API. Use the `requests` library to make HTTP GET requests. Include your API key in the request headers to authenticate. Parse the JSON response to extract the data you need.

```python
import requests

def fetch_coinmarketcap_data(api_key, endpoint='v1/cryptocurrency/listings/latest'):
url = f'https://pro-api.coinmarketcap.com/{endpoint}'
headers = {
'Accepts': 'application/json',
'X-CMC_PRO_API_KEY': api_key,
}
response = requests.get(url, headers=headers)
data = response.json()
return data

Create a Google Cloud project if you haven't already. Enable the Pub/Sub API for your project. Then, create a Pub/Sub topic that will receive the data. Note the topic name, as you will need it to publish messages.

Install the Google Cloud SDK and authenticate using `gcloud auth application-default login`. This will allow your script to interact with Google Cloud services. Set the project ID to ensure all operations are performed within the correct project.

Integrate the Google Pub/Sub client library into your script. Authenticate using the credentials set up previously. Use the `PublisherClient` to publish messages to the topic created in Step 4.

```python
from google.cloud import pubsub_v1

def publish_to_pubsub(project_id, topic_name, data):
publisher = pubsub_v1.PublisherClient()
topic_path = publisher.topic_path(project_id, topic_name)

# Data must be a bytestring
data_bytes = json.dumps(data).encode('utf-8')

future = publisher.publish(topic_path, data=data_bytes)
print(f'Published message ID {future.result()}')
```

To regularly move data from CoinMarketCap to Google Pub/Sub, automate the script using a scheduler. On Unix-based systems, use `cron` to set up a schedule. On Windows, use Task Scheduler. This ensures data is transferred at regular intervals without manual intervention.

```bash
# Example cron job to run the script every hour
0 * * * * /usr/bin/python3 /path/to/your/script.py
```

Ensure your script handles possible exceptions, such as API request failures or network issues, to make the data transfer process robust and reliable.