Ensure you have both IBM Db2 and DuckDB installed on your system. Verify that you have access credentials for Db2 and that you can connect to the database using a Db2 command-line tool or GUI interface. Also, ensure DuckDB is ready for use, typically through its command-line interface or a Python environment.

Use the Db2 command-line tool to export your data into a CSV format. You can achieve this by executing an SQL query that selects the desired data and directs the output to a CSV file. Example command:
```bash
db2 "EXPORT TO /path/to/exported_data.csv OF DEL MODIFIED BY NOCHARDEL SELECT FROM your_table"
```
This command exports the data from `your_table` into a CSV file named `exported_data.csv`.

After exporting, open the CSV file to inspect its contents and ensure data integrity. Check for special characters, proper delimiters, and consistent formatting. This step helps guarantee that the data is correctly formatted before importing it into DuckDB.

Start DuckDB either through its command-line interface or within a Python environment. If using the command line, simply type `duckdb` to begin a session. If using Python, you can start by importing DuckDB with:
```python
import duckdb
```

Within DuckDB, create a new database (if one doesn’t already exist) and a table structure that matches the schema of your CSV data. For example, using DuckDB’s SQL interface:
```sql
CREATE TABLE your_table (
column1_name column1_type,
column2_name column2_type,
...
);
```
Replace `column_name` and `column_type` with the actual column names and data types from your CSV.

Use DuckDB's built-in CSV reader to import the data. This can be done with a SQL command in DuckDB:
```sql
COPY your_table FROM '/path/to/exported_data.csv' (DELIMITER ',', HEADER);
```
This command reads the CSV file and populates the `your_table` in DuckDB with the data.

Once the import is complete, perform a few SQL queries to ensure that the data has been accurately transferred to DuckDB. Check for row counts, sample data comparisons, and data type consistency to ensure the integrity of the import process.
```sql
SELECT FROM your_table LIMIT 10;
```

This 7-step guide allows you to move data from IBM Db2 to DuckDB efficiently without the need for third-party connectors or integrations, focusing on CSV as an intermediary to facilitate data transfer.