Motion guide is basically a path we draw for an object to follow during a motion tween.We can link multiple layers to a motion guide layer to have multiple objects follow the same path.
1. Open a new document by selecting File > New. Select Flash File (ActionScript 3.0), click OK.
2. Now you need to import the image you want to tween.I am going to import a cycle for this motion guide.
3. Place the image in Frame 1
4. Now enter a key frame in frame 30.
a,To do this, first click frame 30 in layer one on the timeline. Then press F6.
b,Right click on Frame 30 and select Insert Key Frame.
5. Now you have to Create Motion Tween.Right click on Frame 30 and select create motion tween
Creating Motion Guide
6.Right click on Layer 1.
A pop-up menu appears.
Choose Add Motion Guide.
Flash now inserts a new layer on top of layer 1.This new layer is called a motion guide layer.
Select the Pencil tool (Y). In the Tools panel, go to the end of it and choose the Smooth option for drawing with your pencil
With the pencil draw the line you want the cycle to move along.
7.Click on the first keyframe of the Cycle layer to select it.
8.View > Snap in the menu, to activate snapping
9.Click on the cycle once to select it – do this with the Selection tool (V).
10.You will move the cycle to the guide’s starting point. Use the Selection tool (V). A black circle appears when the cycle is attached to the motion guide.
11.Click on the Frame 30 in the cycle layer to select it.
12.Place it over the other end of the guide using the Selection tool (V). It should also snap into place, just like before.
13.Press Ctrl+Enter to test your movie.The cycle will now follow the motion guide when you play the movie.