Begin by setting up the AWS SDK for Python, known as Boto3, which allows Python applications to interact with AWS services like DynamoDB. Install Boto3 using pip with the command `pip install boto3`. This will be necessary for accessing and manipulating DynamoDB tables programmatically.

Sentry provides a REST API that you can use to retrieve event data. Familiarize yourself with the Sentry API documentation and obtain an API token by navigating to your Sentry account settings. Use Python's `requests` library to make HTTP GET requests to the relevant Sentry API endpoints to fetch the data you need. For example, you might use an endpoint like `/api/0/projects/{organization_slug}/{project_slug}/events/` to list events.

Parse the JSON responses from the Sentry API to extract the required information. Use Python's built-in `json` library to handle the JSON response data. Create a function that iterates over the API response and structures the data into a format suitable for storage in DynamoDB. Ensure you handle pagination if the data set is large.

In your AWS account, create a DynamoDB table if you haven't already. Define the primary key structure (partition key and optionally a sort key) based on how you plan to query the data. For example, if you are storing Sentry event data, you might use `event_id` as the partition key.

Develop a Python script to automate the ingestion of data into DynamoDB. Use Boto3 to connect to DynamoDB and write the structured data obtained from Sentry into the table. Use the `put_item` method to insert individual records. If dealing with large data sets, consider using `batch_write_item` for more efficient batch processing.

Ensure your script includes robust error handling to manage potential issues such as network failures, API rate limits, or AWS service errors. Use Python's `logging` module to log any errors or significant events during data transfer. This will help in monitoring the process and troubleshooting if necessary.

To keep the DynamoDB data up-to-date with Sentry, consider automating the data transfer script using a task scheduler like cron jobs on Unix-based systems or Task Scheduler on Windows. Determine an appropriate frequency for the data transfer based on your needs, such as hourly, daily, or weekly.

By following these steps, you'll manually set up a process to move data from Sentry to DynamoDB without relying on third-party connectors or integrations.