Google BigQuery and Slack are both powerful tools used by data professionals, making it useful to sync data between them to streamline daily workflows. There are three methods to sync data from BigQuery to Slack: manual, using APIs, and through Census, a no-code automation tool. The manual method involves running a SQL query in BigQuery, saving the result to a file, and then uploading it to Slack. This method is straightforward but time-consuming for frequent use. The API method requires coding and setting up APIs, which can be more involved but provides flexibility. Census offers a third option, allowing users to automatically sync data with notifications on updates, making it an efficient choice for regular syncing.