Start by exporting the data you need from CockroachDB. Use the `cockroach dump` command to export data in SQL format. This command allows you to extract the schema and data for the desired tables. Here's an example command:
```
cockroach dump my_database --insecure --host=my_host --user=my_user --format=csv > my_data.csv
```
This will generate a CSV file containing your data.

Before importing data into Snowflake, ensure that the CSV file is properly formatted. This involves checking for consistency in delimiters, handling any special characters, and ensuring that the date formats are compatible with Snowflake. You may need to clean or transform the data using a script or a CSV editor.

A stage in Snowflake is a location where you temporarily store data files. Use the `CREATE STAGE` command to create an internal stage. This stage will be used to hold your CSV file before loading it into a table:
```sql
CREATE STAGE my_stage;
```

Use the Snowflake web interface or the SnowSQL command-line client to upload the CSV file to the stage you created. If using SnowSQL, the command would look like this:
```
snowsql -q "PUT file://path/to/my_data.csv @my_stage"
```

Define the schema for the target table in Snowflake where the data will be loaded. Ensure that the data types and structure match your CSV file. Here's an example:
```sql
CREATE OR REPLACE TABLE my_table (
column1 STRING,
column2 INTEGER,
column3 DATE
);
```

Use the `COPY INTO` command to load the data from the stage into the Snowflake table. Specify the file format and any necessary transformations (e.g., NULL handling, date format changes):
```sql
COPY INTO my_table
FROM @my_stage/my_data.csv
FILE_FORMAT = (TYPE = 'CSV' FIELD_OPTIONALLY_ENCLOSED_BY = '"' SKIP_HEADER = 1);
```

After loading, verify that the data in Snowflake matches the source data from CockroachDB. Run queries to check row counts, data integrity, and specific data points. Once confirmed, clean up by removing the file from the stage if it's no longer needed:
```sql
REMOVE @my_stage;
```

Following these steps will allow you to move data from CockroachDB to Snowflake manually without the need for third-party connectors or integrations.