Create a VM from the instance template, then a custom image from the VM’s disk. Export the image to Cloud Storage and set up an HTTP load balancer with the Cloud Storage bucket as its backend service.

Set up an unmanaged instance group using the instance template. Configure autoscaling for HTTP traffic and use the instance group as the backend service for an HTTP load balancer.

Deploy instances based on peak traffic estimates using the instance template. Form an unmanaged instance group with these instances and assign it as the backend service for an HTTP load balancer.