To prepare for the upcoming peak traffic season following Google-recommended practices, the first step should be to understand the current performance and scaling capabilities of the application under load. This involves load testing the application to profile its performance for scaling (Option C). Load testing helps identify bottlenecks and the application's behavior under stress, which is crucial for making informed decisions about scaling and infrastructure changes. While migrating to Cloud Run with autoscaling (Option A) and creating Terraform configurations for quick deployment (Option B) are good practices, they should be considered after understanding the application's performance through load testing. Pre-provisioning compute power based on last season's usage (Option D) is not a scalable or efficient approach, as it does not account for potential growth or changes in traffic patterns.