Updated README.

README.md

@@ -8,8 +8,31 @@ HTTPie is a CLI frontend for [python-requests](python-requests.org).
     pip install httpie
 
 
+### Usage
+
+    httpie [flags] METHOD [header:value data-field-name=value]* URL
+
+The default request `Content-Type` in `application/json` and data fields are automatically serialized as a JSON `Object`:
+
+    httpie PATCH  name=John api.example.com/person/1
+
+That will issue the following request:
+
+    PATCH /person/1 HTTP/1.1
+    User-Agent: HTTPie/0.1
+    X-API-Token: 123
+    Content-Type: application/json; charset=utf-8
+
+    {"name": "John"}
+
+
+The data to be sent can also be passed via `stdin`:
+
+    httpie PUT X-API-Token:123 api.example.com/person/1 < person.json
+
+The flags mirror many of the arguments you would use with `requests.request`. See `httpie -h` for more details.
+
+
 ### Screenshot
 
 ![httpie](https://github.com/jkbr/httpie/raw/master/httpie.png)
-
-