Update 'README.md'

README.md

@@ -7,4 +7,8 @@ The script `booklet.sh` generates two PDFs:
 
 To run the script, you can use the following command:
 
-`$ bash booklet.sh`
+`$ bash booklet.sh WIKIPAGENAME`
+
+So in our case:
+
+`$ bash booklet.sh Pen_plotters`