flash MX or sothink
or you can use websites to do it as :

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dowload adobe flash
Create a new Flash file. Go to the properties panel and specify dimensions of 468 pixels by 60 pixels. This is the standard Web size for a full banner as recommended by the Interactive Advertising Bureau, or IAB.
then Draw or write in the image editing area or on the "stage" as you would in any image editing application. Use the toolbox to find paintbrush, pencil, shape tool and text editing tools. You are drawing in the first layer, which is highlighted in your time line. For each additional element that you wish to animate, you will need to add a new layer. Flash creates each animation (e.g. an arm moving) as a single process, so it's important to have just one element per layer. They will all be visible by default in the time line.
Go to the time line, and click on the "New layer" button. Name your layer by clicking on the newly created layer's name, usually "Layer 2" and typing your new layer name.
Return to your stage. Draw or write your next element using the drawing and text tools. Repeat adding a new layer and drawing for every element that you will animate. Use a separate layer for background and non-animated elements.
Go to the point in your time line where you wish to see an animation effect for a particular layer. With the layer selected, right-click on that frame and click on "Create keyframe." This will duplicate your first frame for that layer. Adobe Flash plays your animations as if they were a movie, so the frame numbers are related to the point in time in which they appear. The standard frame rate for Flash in Adobe's Creative Suite 4 package is 24 frames per second: For each second elapsed, 24 frames will be played. If you want an animation that lasts for 1 second, for example, go to Frame 24, for 2 seconds go to the Frame 48 and so on.
Change the text or image into what you want---simple but effective animations are size changes, moving an element across the frame or changing a shape or color. You can change the size of a shape by right-clicking on it and clicking on the "Free transform" button. To warp its shape, use the "Subselection" tool, the white arrow or second icon in the toolbox.
Right-click in the space between the two keyframes, and click "Create classic tween" if you moved an element across the stage. Alternatively, click "Create shape tween" if you changed the size or shape of an object.
Create keyframes for all the layers you wish to keep visible until the final frame. Otherwise, they will be hidden after the first frame.
Repeat the process of creating keyframes and tweening for every other piece of animation you wish to create. Remember that the layers have separate animations, but these will be played together like a movie.
Go to the "Control" menu, and click "Test movie". This will allow you to see if your banner looks and plays the way you want it to.
Go to the "File" menu, and click on "Export movie". Save your banner as a .swf file.
use these steps for making your own flash banner