Summarize this article in one sentence.
If you'd rather convert a video to an animated GIF format, see How to Make an Animated GIF from a Video in Photoshop CS5. A working knowledge of Photoshop tools will help you immensely with this method. See How To Use Adobe Photoshop Tools for general Photoshop tips.  Open the “File” menu and click “New” to view options for your new file. Type a name for your animation in the box next to “Name.” In the “width” and “height” boxes, note the measurement types after the value boxes. It's either set to inches or pixels, depending on what you've used in the past. If you feel comfortable specifying pixel size, change the measurement type to “Pixels.” If it's easier for you to visualize inches, choose that option. Type your desired measurement in its corresponding box. Choose a background color for your animation. Click the menu next to “Background” or “Background contents” (depending on your version of Photoshop) and choose from the color options. Click “OK” to create your new image with these settings. Each frame of your animation needs to be in its own layer, so you'll want the layers panel visible. Click the Window menu and check both Layers and Animations. The panels will then appear in your workspace. In the Layers panel, click the plus sign (+) to add a new layer. Next to “Name,” type a name for your layer, such as “Frame 1.” Set the Fill color either to Transparent or the color of your background. Click “OK” to create this new layer. Each element of your animation needs to be on a unique frame. Anything you put on this new layer will animate as one frame. If you want to draw on this layer, choose a color from the swatch panel (the panel with all of the colored squares) then click the paintbrush tool. If you want to add text, click the “T” to launch the text tool. Create another layer and build the second frame of your animation.  If the next frame of your animation will simply be a slight modification to the first frame, you may want to “Clone” your layer instead of creating a new one. To clone the layer, right-click on that layer in the Layers panel and select “Duplicate layer.” Continue creating or cloning layers until you have each individual frame of your animation on its own layer. In the Animation panel at the bottom of the screen, click the icon that is a small rectangle with a smaller square on top of it (the New Frame button). This will create one new frame. Click this button as many times as there are layers in your animation. If your animation will have 7 layers, create 7 frames. Click the first frame in the panel. As you can see from the thumbnail, this frame presently consists of every layer in your animation.  Notice that each layer in your Layers panel has a small eyeball symbol next to it. This symbol tells you that the layer is currently visible. To make the first frame in the Animation panel display only the first layer, remove the eyeball symbol from each of the other layers. Change the duration for this frame by adjusting the time (in seconds) beneath the thumbnail, which currently reads “0 sec.” Click each additional frame and remove visibility from all layers other than the one you want to be visible in the frame. Remember to adjust the time at the bottom of each thumbnail. The Play button is located beneath the animation frames at the bottom of the screen. Click “File,” then “Save for Web and Devices.” Make sure that GIF is selected in the top pulldown menu beneath the word “Preset” and click “Save.”

Summary:
Create a new image in Photoshop. Open the Layers and Animation panels. Create a new layer for your first frame. Add your text or drawing to your new layer. Create your next frame. Create new frames in the Animation panel. Edit the contents of the first frame in the Animation panel. Edit subsequent frames. Press the Play button to test your animation. Save the animation as a GIF.