ok, so you are wondering how you can do an animation gif. well im gonna show you.

1. open photoshop

2. create new file (CTRL + n) with these properties:
20080717--op-animation-new.jpg

3. Now on the new file add an arrow witht he custom shape tool
20080717-6230--animation-arrow.jpg

4. now you want to edit the arrow image with image ready, so click on the icon or you can hit (CNTL + SHIFT + M)
20080717-6230ation-imageready.jpg

5. now when you export to animation ready, youll have three windows, that look something like this:
20080717_6230_-animation-panel.jpg

6. now add a new frame by clicking on the little arrow on the far right in the animation box
20080717_6230_imation-newframe.jpg

7. now remove visability on both layers in the layer window and the box (2) in the animation box will become transparent. we want it to be blank so that when the animation cycles, it will look like its flashing, sow the layer and animation windows should look like this now:
20080717_6230_ation-visability.jpg

8. as you can see from the image above box 1 and box 2 in the animation window are set for 0 sec. so we want to change the timing to 5 sec on both boxes. make sure you select forever loop
20080717_6230_animation-timing.jpg

9. now you are ready to see it in action. hit (CTRL + ALT + P) to preview in your browser, you should see the arrow flashing like this:
20080717_6230_n-flashing-arrow.gif

10. now you can just save it from your browser.

done