diff --git a/README.md b/README.md
index 244390f..4249d25 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,13 @@
 # python-csr
 Generate a key, self-signed certificate, and certificate request.
 
-Usage: csrgen <fqdn>
+Usage: csrgen [fqdn]
+
+Example: python csrgen test.test.com
 
 When more than one hostname is provided, a SAN (Subject Alternate Name)
 certificate and request are generated.  This can be acheived by adding -s.
 
 Usage: csrgen <hostname> -s <san0> <san1>
+
+Example: python csrgen test.test.com -s mushu.test.com pushu.test.com