1. Click a layer name to make it the active layer, and create or select a keyframe where you want the animation to start.
2. Create or place the artwork for the first frame of the sequence. For best results, the frame should contain only one item (a graphic object or broken-apart group, bitmap, instance, or text block).
3. Select the keyframe in the Timeline.
4. Select Window > Properties.
5. In the Property inspector, select Shape from the Tween pop-up menu