update readme

packages/omiu/README.md

@@ -2,11 +2,48 @@
 
 > Omi ui.
 
-Simple UI framework, compatible with omi and omio.
+Simple UI framework, compatible with omi and omio(IE8+), using the design style of Wechat 7.0.
 
 * [English Docs](https://tencent.github.io/omi/packages/omiu/examples/build/index.html)
 * [中文文档](https://tencent.github.io/omi/packages/omiu/examples/build/zh-cn.html)
 
+## Use it immediately
+
+```
+npm i omi-cli -g             
+omi init my-app   
+cd my-app           
+npm start                     
+npm run build    
+```
+
+> `npx omi-cli init my-app` is also supported(npm v5.2.0+).
+
+## Use it in existing project
+
+```js
+npm i omiu
+```
+
+```js
+import { WeElement, define, render } from 'omi'
+import 'omiu/button'
+
+define('my-app', class extends WeElement {
+  onClick = () => {
+    console.log('Hello omiu!');
+  }
+
+  render() {
+    return (
+      <o-button onClick={this.onClick}>I am button.</o-button>
+    )
+  }
+})
+
+render(<my-app />, 'body')
+```
+
 ## Development 
 
 ```bash