In this Macromedia Flash tutorial I will show you how to make a guide line and how to animate an object so it follows the guide. Keep in mind this is a basic tutorial and explaind so even beginners may have a change to follow it.

1.
In the layers panel right click the new empty layer and choose add motion guide as shown below.
Now you will see two layers, the top layer it where you should draw your line. The bottom layer is where the object you want to animate should be drawn.

2.
Select the top layer, and with the line tool draw a simple line as shown below, then move the mouse cursor close to the lines and drag out the lines to make curves for a more smooth guide line.

3.
Now select the bottom layer, draw in a shape, I just made an oval with a gradient, but feel free to be more creative and make more complex shapes.

4.
Right click your shape and choose convert to movie clip.
In frame 1 move the shape to the start point of your guide line as I did below.

5.
In the time line select keyframe 40 for both layer and right click, insert new keyframe.
In the bottom layer right click at frame 20 and insert a new keyframe.

6.
At frame 20 move your shape all the way to the right.
Now select the frame in between frame 1 and 40 in the bottom layer.Right click and choose add motion tween.

And you are done. Now try your flash animation, and you will see that your shape does follow the guide line you just made.