Update README.md

Author: maxazan

README.md

@@ -23,10 +23,45 @@ Download [source](https://github.com/maxazan/angular-multiple-selection/archive/
 
 ##Using
 * Add `multiple-selection.min.js` file to your application
-```
+```html
 <script type="text/javascript" src="multiple-selection.min.js"></script>
 ```
 * Add module to your app `angular.module('app', ['multipleSelection'])`
 * Add `multiple-selection-zone` attribute to element where selectable items will be located
 * Add `multiple-selection-item` attribute to each selectable item
 * Customize css
+
+
+##How it works
+Each selectable item has it`s own angular scope with variables
+
+| Name  | Description |
+| ------------- | ------------- |
+| isSelectable  | `true` if element can be selected |
+| isSelecting  | `true` if element now selecting. It means it enters in selection rectangle when you dragging |
+| isSelected  | `true` if element selected |
+
+###How to customize
+
+* Add `ng-class` to your item
+```html
+<div multiple-selection-item ng-class="{'selecting': isSelecting ,'selected': isSelected}"></div>
+```
+* Customizing `.selecting` and `.selected` in your css
+```css
+.selected {
+    background-color: green !important;
+}
+.selecting {
+    background-color: yellow !important;
+}
+```
+* You can also customize your rectangle for selecting
+```css
+.select-helper {
+      position: absolute;
+      border: 1px dashed red;
+      background: red;
+      opacity: 0.2;
+}
+```