diff --git a/README.md b/README.md
index f2e44f8..c92d925 100644
--- a/README.md
+++ b/README.md
@@ -26,10 +26,9 @@ Here's a list of sample `Dockerfile`s that install the GD and xdebug PHP extensi
 ```Dockerfile
 FROM php:7.2-cli
 
-ADD https://github.com/mlocati/docker-php-extension-installer/releases/latest/download/install-php-extensions /usr/local/bin/
+ADD --chmod=0755 https://github.com/mlocati/docker-php-extension-installer/releases/latest/download/install-php-extensions /usr/local/bin/
 
-RUN chmod +x /usr/local/bin/install-php-extensions && \
-    install-php-extensions gd xdebug
+RUN install-php-extensions gd xdebug
 ```
 
 ### Downloading the script on the fly with `curl`