AWS CloudFormation is a robust Infrastructure as Code (IaC) service that simplifies the management of AWS cloud resources through declarative JSON or YAML templates, enabling automated, scalable, and reproducible infrastructure deployments. The service allows users to define their desired infrastructure state and manages the orchestration of AWS resources, supporting over 200 services. CloudFormation templates, central to this process, describe the configuration and relationships of resources like EC2 instances, VPCs, and RDS databases. This guide emphasizes best practices such as integrating CloudFormation with CI/CD pipelines, organizing and reusing templates, and using advanced features like nested stacks, custom resources, and change sets for modularity and error handling. The article also highlights Earthly, a build automation tool that enhances CloudFormation workflows by allowing users to script and automate deployment processes, aligning with CloudFormation's best practices for infrastructure management.