First, export the data from ClickHouse into a file format that can be easily transferred. Use the `clickhouse-client` tool with the `--query` option to export data. Choose a format like CSV for simplicity. For example:
```
clickhouse-client --query="SELECT * FROM your_table" --format=CSV > data_export.csv
```

Ensure you have access to your Firebolt account and have the necessary permissions to create tables and import data. Log in to your Firebolt account and identify or create the database and table structure that will receive the data from ClickHouse.

Before importing data, create the table in Firebolt that matches the schema of your ClickHouse data. Use the Firebolt SQL Editor to execute a `CREATE TABLE` statement. Ensure that the data types and column names match the exported data:
```sql
CREATE TABLE your_table (
column1 DataType1,
column2 DataType2,
...
);
```

Upload the exported CSV file to a storage location accessible by Firebolt. This could be an S3 bucket or another cloud storage solution. Ensure that Firebolt has the necessary permissions to access this storage location.

Use the Firebolt `COPY INTO` command to load your data from the storage location into your Firebolt table. Execute a SQL command similar to the following:
```sql
COPY INTO your_table
FROM 's3://your-bucket/data_export.csv'
CREDENTIALS = (aws_key_id='your_key' aws_secret_key='your_secret')
FILE_FORMAT = (TYPE = CSV);
```

After loading the data, perform checks to ensure that the data in Firebolt matches the original data in ClickHouse. Use SQL queries to count records, sum numerical columns, or perform other checks to verify that the data has been imported correctly:
```sql
SELECT COUNT(*) FROM your_table;
```

Finally, optimize the loaded data for performance by creating appropriate indexes and partitions. Firebolt allows you to create primary indexes and other optimizations to enhance query performance:
```sql
CREATE INDEX idx_column1 ON your_table (column1);
```

By following these steps, you can successfully move your data from ClickHouse to Firebolt without relying on third-party connectors or integrations.