Do keep a gitops folder / repository to keep your cluster in sync with expectations, do not let adhoc edits become the norm.

Use tools like kustomize to reduce proliferation of duplicate k8s resource files.

Do make sure you are using health and liveness checks.

Definitely take care to specify resource requests and limits.

Do use annotations to control provider resources, rather than manually tweaking provider resources that are auto generated by basic k8s files with no annotations.

Aggregate your logs.