docs: cover diffing/applying manifests to cluster
```bash
kubectl rollout status deployment.v1.apps/chime
```
+
+## Applying Changes to `k8s/` Manifests
+
+After making changes to the manifests in `k8s/` that you want to apply, first review the diff for what you're about to change using an editor that wil color-code the output and make it easy to review:
+
+```bash
+kubectl diff -Rf k8s/ | code -
+```
+
+*Ignore any instances of `generation` being incremented*
+
+Once you're satisfied with the results of the diff, you can apply a single manifest:
+
+```bash
+kubectl apply -f k8s/infra/ingress-nginx.yaml
+```
+
+Or the entire directory:
+
+```bash
+kubectl diff -Rf k8s/
+```
