As your last few steps, convert the 1st frame of your animation to "index color" and then convert the rest of the frames with the setting of the "Previous" image (ALT+M+I+P). Now save each frame as a different gif file. Now load Gif Construction Set & import all of your frames. Then copy the 2nd to last frame and make it your last frame. Continue this until you reach the 1st frame (the flat image). This creates the rotating effect on your image. (In the CONTROL settings in GCS, I set the dark gray color to be transparent color. Because the palettes is the same for each image all grays were taken out.) Save your animation and your done.

Note: This tutorial is if you want to see just the front of the image. If you want to see the front & back as if it is spinning a complete 360 degrees. Duplicate the images, then take one set of copies and flip them horizontally.

Another Note: This tip is to create an illusion of a spinning object. Most of the 3D animations that I have created have to be done in a 3D program and can't be done with a paint program such as Photoshop.