Step 11
It's time for snow animation, so create a new layer and name it "snow fall". Lock all layers except snow fall layer, select it, teke the Brush Tool (B), for brush size choose minimal, for fill color choose white color, and draw two points on the top of header, that will represent "snow flake". Look at the picture below!


Step 12
Select it ("snow flake") and convert it into a Movie Clip.

Step 13
Double-click on the movie clip on stage with the Selection tool (V) .You should now be inside the movie clip.

Step 14
Select only the one "snow flake", press Ctrl+C key (Copy), create a new layer (layer 2), select it and press Ctrl+Shift+V (Paste in Place).
Step 15
While you're still on layer 2, select it and press F8 key (or select Modify > Convert to Symbol ) to convert this "snow flake" into a Graphic Symbol.

Step 16
Repeat the previous step for layer 1. Now you have two "snow flakes" converted into a Graphic Symbol.
Step 17
It's time for Motion Guide, so right-click on layer 2, and choose Add Motion Guide from the menu that appears. See the picture below.

Now, you have this:

Step 18
Select the Guide layer, take the Pencil Tool (Y), for Stroke Color choose black, in Pencil Option choose Smooth, and draw for both "snow flake" "path", that they will folow. See the picture below.


Step 19
Click on frame 60 of layer guide and press F5 key. After that take the Selection Tool (V), and move the first layer above the layer 2. See the picture below.

Step 20
Click on the first frame of layer 1, place the "snow flake" on the top of "path". After that, click on frame 60 and press F6 key (Keyframe). Then, place the "snow flake" on the bottom of "path". See the pictures below.


Step 21
Right-click anywhere on the gray area between the two keyframes on the timeline and choose Create Motion Tween from the menu that appears. Repeat this steps for every other "snow flake" in an equivalent way.