Update README.md

Author: spinningwatt

README.md

@@ -1,2 +1,11 @@
 # BezierTool
 A bunch of scripts for better orbit arrangement in Unity
+## Usage
+### 1.Import Unitypackage
+Assets->Import Package->Custom Package, then choose the package downloaded from release.
+### 2.Drag a script on the Object
+After import the package, there should be three more folders in your project. Get into the folder *BeizerTool*. Drag the script *BezierDriver.cs* onto the object(s) you want to control.
+### 3.Adjust the parameters
+Select the object in *Hierarchy*. There are three control points in the *Scene* by default. You can drag the handle to adjust the orbit which is drawn with white dash. To add more control points, input the number of control points you need in the filed named *size* under *Ctrl Points* in *Inpector*.
+### 4.Check the result
+Click on *Play*. Check the orbit of objects.