Begin by exporting the data you need from Chargebee. Navigate to the Chargebee dashboard, locate the "Reports" or "Data Export" section, and select the specific datasets you require. Export these datasets in a CSV format, which is commonly supported and easy to work with for subsequent steps.

Set up your local environment to handle the CSV files. Ensure you have tools like Python or SQL installed to process and manipulate the data if necessary. You might also need command-line tools like `csvkit` for any preliminary checks or transformations on your CSV files before uploading them to Snowflake.

Using your preferred data processing tool (such as Python with pandas), load the CSV files and perform any necessary data transformations or cleaning. This step ensures that the data is in the correct format and free of any inconsistencies or errors that could cause issues during the import process. Save the cleaned data back into a CSV file.

Log in to your Snowflake account and create a stage where you can temporarily store your CSV files before loading them into Snowflake tables. Use the following SQL command to create an internal stage:
```sql
CREATE STAGE my_stage;
```

Use SnowSQL, Snowflake's command-line client, to upload your CSV files to the stage you created in the previous step. Execute the following command in your terminal, substituting the file path and stage name as necessary:
```bash
snowsql -q "PUT file://path/to/your/file.csv @my_stage"
```

Once your files are in the stage, load them into Snowflake tables. First, ensure that you have created the necessary tables to hold your data. Then, use the `COPY INTO` command to load the data from the stage into your Snowflake table:
```sql
COPY INTO my_table
FROM @my_stage/file.csv
FILE_FORMAT = (TYPE = 'CSV' FIELD_OPTIONALLY_ENCLOSED_BY = '"');
```

After loading the data, perform data checks to verify integrity and completeness. Use SQL queries to validate that all rows have been imported correctly and that there are no discrepancies. Compare the number of records and key statistics with the original CSV files from Chargebee to ensure accuracy.
By following these steps, you can successfully transfer data from Chargebee to Snowflake without relying on third-party connectors or integrations.