diff --git a/README.nd b/README.nd
index 8c20e15..2c99cb4 100644
--- a/README.nd
+++ b/README.nd
@@ -4,6 +4,7 @@ Useful for ancient devices, but TOTALLY NOT SECURE!
 
 ```copy example config and edit
 cp config.example config
+chmod 600 config
 $EDITOR config
 ```