diff --git a/README.md b/README.md
index d4061026f82214d4bddccd8a329a789c1f154395..78f12978e98adcd415caf19d0ca12cab52dd33f4 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Installation
 ------------
 
 	$ sudo apt install python3 python3-dev python3-pip -y 
-    $ pip3 install --upgrade pip
+	$ pip3 install --upgrade pip
 	$ pip3 install datetime shade tqdm python-openstackclient
 	$ git clone https://git.garr.it/cloud/admin/update-images.git
 
@@ -33,7 +33,7 @@ Execute the script
 
 ### Execution example
 
-    $ python3 update-images.py
+	$ python3 update-images.py
 	Download...
 	From: http://cloud.centos.org/centos/7/images/CentOS-7-x86_64-GenericCloud.qcow2
 	To:   downloads/centos7-1505262668.qcow2
@@ -53,14 +53,14 @@ This script uploads all the images as 'Public', accessible by all users.
 ### Update simplestreams
 After updating the images, update the simplestreams catalog:
 
-    $ openstack object list simplestreams
-    $ openstack object save simplestreams images/streams/v1/com.ubuntu.cloud-released-imagemetadata.json --file com.ubuntu.cloud-released-imagemetadata_backup.json
-    $ openstack object save simplestreams images/streams/v1/index.json --file index_backup.json
+	$ openstack object list simplestreams
+	$ openstack object save simplestreams images/streams/v1/com.ubuntu.cloud-released-imagemetadata.json --file com.ubuntu.cloud-released-imagemetadata_backup.json
+	$ openstack object save simplestreams images/streams/v1/index.json --file index_backup.json
 
 	$ python3 generate-files-for-simplestream.py
-    $ cd output/simplestreams
-    $ ls -lh images/streams/v1/
-    $ openstack object create simplestreams images/streams/v1/com.ubuntu.cloud-released-imagemetadata.json images/streams/v1/index.json
+	$ cd output/simplestreams
+	$ ls -lh images/streams/v1/
+	$ openstack object create simplestreams images/streams/v1/com.ubuntu.cloud-released-imagemetadata.json images/streams/v1/index.json
 
 
 Pipeline