diff --git a/utils/post_cert_renewal/post_cert_renewal.sh b/utils/post_cert_renewal/post_cert_renewal.sh
index 39d75ce1..2ee902c0 100755
--- a/utils/post_cert_renewal/post_cert_renewal.sh
+++ b/utils/post_cert_renewal/post_cert_renewal.sh
@@ -1,4 +1,8 @@
 #!/bin/bash
+
+# copy this script into /etc/letsencrypt/renewal-hooks/post
+# to test: sudo certbot renew --dry-run
+
 # copy the certificates into /etc/vernemq
 cp -Lp /etc/letsencrypt/live/resqapi.jankstudio.com/*.pem /etc/vernemq