some tip in readme

README.md

@@ -12,9 +12,44 @@ $ npm install sequelize-fixture
 
 ## Usage
 
-```js
+```nodejs
 var Sequelize = require('sequelize');
 
 require('sequelize-fixture')(Sequelize);
 
+
+it('should generate fixture base on define of Model', function () {
+    var Foo = sequelize.define('Foo', {
+      title: Sequelize.STRING(64),
+      string: Sequelize.STRING,
+      text: Sequelize.TEXT,
+      bool: Sequelize.BOOLEAN,
+      num: Sequelize.INTEGER,
+      bignum: Sequelize.BIGINT,
+      float: Sequelize.FLOAT,
+      date: Sequelize.DATE,
+      uuid: Sequelize.UUID,
+    });
+
+    var fixture = Foo.fixtures();
+    assert.ok(fixture.title);
+    assert.ok(fixture.string);
+    assert.ok(fixture.text);
+    assert.equal(typeof fixture.bool, 'boolean');
+    assert.ok(fixture.num);
+    assert.ok(fixture.bignum);
+    assert.ok(fixture.float);
+    assert.ok(fixture.date);
+    assert.ok(fixture.uuid);
+});
 ```
+
+more usage see my test
+
+[datatypes_test](https://github.com/xudejian/sequelize-fixture/blob/master/test/datatypes_test.js)
+[model_test](https://github.com/xudejian/sequelize-fixture/blob/master/test/model_test.js)
+[associate_test](https://github.com/xudejian/sequelize-fixture/blob/master/test/associate_test.js)
+
+## Pull Request Welcome
+
+Thank you!