Blue-Green Deployments are a strategy for seamless software updates that involve maintaining two identical environments, "blue" (staging) and "green" (production), to facilitate zero-downtime releases and easy rollbacks. This guide explains how to set up Blue-Green Deployments using Kubernetes and Harness, outlining a step-by-step process to create applications, services, environments, and workflows. Key steps include creating a new application and service, setting up a production environment, and configuring a Blue-Green Deployment workflow, which Harness simplifies with automated health checks and verification processes. The deployment process allows the traffic to be switched from the green to the blue environment once the new version is validated, with optional rollback procedures and templating options for reusability by different development teams. This setup enhances deployment efficiency by enabling continuous delivery while minimizing risks, and it supports automation and manual approvals for greater control over the release process.