How to create basic motion in after effects using a still image?

Our Photoshop Image
Alex Costaris-102156184

http://www.adobe.com/ap/motion/tips/aftbdrop/page2.html



Step 1:
Create a layered Photoshop image.
Put each element you want to animate on its own layer. Design each layer so that its left and right edges meet seamlessly when the image is offset (repeated horizontally). Make the image the same size as the After Effects composition.
In After Effects, you'll be using the Offset effect to repeat and animate each image horizontally.

Step 2:
Import the Photoshop file into After Effects.
Choose File > Import > File, select the Photoshop file, choose Composition from the Import As menu, and click Import. After Effects imports the layered Photoshop file as a layered composition in the Project window, along with a folder of the individual footage items that make up the composition's layers.
Double-click the composition in the Project window to open the Timeline and Composition windows containing the Photoshop layers.








Step 3:
Adjust the duration of your composition.
Choose Composition > Composition Settings. Change the Duration to the desired amount, and then click OK. This example project is 30 seconds.
This is a good time to check the composition's frame rate. This project has a frame rate of 30 frames per second.





Step 4:



Increase the duration of the still images to match the new duration of the composition.
You can increase the duration of multiple still images in the Timeline window.
In the Timeline window, drag the blue current-time marker to the end of the composition, or press the End key. Next, click the first layer and Shift-click the last layer to select all the layers. Press Alt+] (Windows) or Option+] (Mac OS) to trim the layer durations to the current-time marker.
Note: You can lengthen a still image to any length, but you can lengthen video footage only to its original duration, unless you time-stretch it.





Step 5:



Use the Offset effect to both tile and animate the cloud layers in one step.
Set the current time to 00:00; then, in the Timeline window, Ctrl-Click (Windows) or Command-Click (Mac OS) to select the layers that you want to animate. This key modifier allows for noncontiguous selection of layers. Activate the Composition window and choose Effect > Distort > Offset. The Effect Controls window appears with an Offset effect tab for each layer you selected.
Offset effect: This effect repeats a layer, lining up the layer copies edge to edge. When you animate this effect, the repeating layer slides across the Composition window as if the image copies were wrapped around behind it in a continuous strip.





Step 6:



Set beginning keyframes.
In the Effect Controls window, click the tab and select the Shift Center To stopwatch for each layer you are animating. Leave the default values, which are the current position coordinates for the layers.
In the Timeline window, select each layer you want to animate and press the U key to display the animated properties in the Timeline window for all selected layers.