Update README

Add description about the improvement.

README.md

@@ -2,3 +2,17 @@ Shorten-URL
 ===========
 
 An Alfred workflow, it can help you to short your URL very quickly.
+
+This is a fork of https://github.com/hzlzh/AlfredWorkflow.com/tree/master/Sources/Workflows/Shorten-URL, the different is if you already copy a url in your clipboard, you can get the result without paste the url into Alfred box, it good for lazy guy :smile:
+
+### How it works
+
+1. Copy a url, for instance `google.com`
+2. Just type `short` in Alfred box(Don't need past url into the box, that's the difference with original one) ![Don't need past URL into the box](https://raw.githubusercontent.com/ilstar/Shorten-URL/master/short.png)
+3. Done!
+
+Of course, you can type/paste the url into the box if you like, it's compatibility with original one.
+
+### Download
+
+https://github.com/ilstar/Shorten-URL/releases