Begin by exporting the desired data from Pardot. Log into your Pardot account and navigate to the data you wish to export, such as lists, reports, or custom objects. Use Pardot’s built-in export functionality to download the data as a CSV file, which is a common format for data transfer.

Once you have the CSV file, open it using a spreadsheet application like Excel or a text editor. Review the data to ensure it is correctly formatted and clean. Remove any unnecessary columns or rows, and ensure that all data types are consistent (e.g., no mixed data types in a column).

If you haven't already, install DuckDB on your system. DuckDB is an in-process SQL OLAP database management system. It can be installed via package managers, downloaded as a standalone binary, or integrated into your application. Follow the official [DuckDB installation guide](https://duckdb.org/docs/installation/) for your specific operating system.

Open a terminal or command prompt and launch DuckDB. Create a new database or open an existing one using the following command:
```
duckdb my_database.db
```
This command creates (or opens) a database file named `my_database.db` in your current directory.

Within the DuckDB CLI or your application, define a table schema that matches the structure of your CSV data. Use SQL `CREATE TABLE` statements. For example:
```sql
CREATE TABLE pardot_data (
id INTEGER,
name VARCHAR,
email VARCHAR,
created_at TIMESTAMP,
-- Add additional columns as needed
);
```

Use DuckDB's CSV import functionality to load your data into the database. Execute the following SQL command within the DuckDB environment:
```sql
COPY pardot_data FROM 'path/to/your/file.csv' (AUTO_DETECT TRUE);
```
Replace `'path/to/your/file.csv'` with the actual path to your CSV file. The `AUTO_DETECT TRUE` option allows DuckDB to automatically infer column types, or you can specify column types explicitly if needed.

After loading the data, run a few queries to ensure everything imported correctly. For instance, you can use:
```sql
SELECT * FROM pardot_data LIMIT 10;
```
Check for any discrepancies in the data import and verify that all columns and data types are as expected. Make necessary adjustments and re-import if required.

This guide provides a straightforward method to manually move data from Pardot to DuckDB, ensuring you maintain full control over the process without relying on third-party connectors or integrations.