Infrastructure as Code (IaC) is a crucial method for managing infrastructure by defining resources in code. To optimize IaC, teams should follow best practices such as organizing repositories with consistent naming conventions and choosing appropriate repository management strategies like Monorepo or Polyrepo. Spacelift enhances this process by providing features like Space structure planning, IDP groups for scalability, regular permission updates, plan policies, and collaboration tools. Additionally, teams should focus on code modularity, variable usage, automation of testing and deployment, and fostering a collaborative environment to ensure consistent, secure, and reliable infrastructure management.