The only thing I know how to use is GIMP.
So, here's my GIMP .gif animation brief tutorial thing:
First, have each frame a separate layer. The first one (base image) must have the layer named "Background (200ms)" (change the number before "ms" to adjust the speed. Smaller numbers = faster speed).
Every layer after that must be: "Frame 2 (200ms) (replace)" and onward (don't start at 1, though ;o)! The frame after that will be "Frame 3 (200ms) (replace)"...etc. I always use "replace" because it replaces the image and seems more simple. Not including that will stack the images, I believe. And, of course, you can adjust the ms.
Finally, save it as an animated .gif and you're all set! :-)
Like this: