I use a program called "Animation shop 3"
It came together with paintshop pro as a discount when I bought that. I don't know what other programs people use.
(and my signature is not actually animated at the moment so for this I of course didn't use animationshop)
What I did was make the frames I want to have in there, and save them as individual pictures. Often following the formula of: 1. Name, 2. Hol id, 3. Hol House, 4. Quote.
So that means: making the base. Save that. Then add those four (or whatever else you might like) categories to the base one at a time and save it. Then put them all in the program to make gifs that you use, in the order that you want them.
Then add transitions. I chose fading in and fading out for all mine, and how quick you want that transition to be. (you'll note that it now makes a LOT of pictures in a row, that's to accomplish that effect. Then save it as a gif, and voila, you've made a gif!
But taking a trip down memory lane
My signature from 1st to 3rd year. I've chosen the 2nd year one, but except for the year and the font it didn't change (permanently) in that time.
As part of a duck duck goose thread, my forefeit was to change my signature and avatar to have a lovely beard
I like the font better in this one. It was far more legible. So I am happy with that change.
This was for a summer camp where my group was the crowned eagles. Ah, good memories.
Not an animated one, but for the Blue and Bronze olympics in 2011. Our team were the muses. We were five members
I made this animated one for a friend.
The one I am currently using has the sigil of Eärendil who is a character in Tolkien's works. He does not appear in the lord of the Rings, but in the Silmarillion. But for those of you who remember this scene (I think it was the extended edition, but I might be wrong) where Galadriel gives Frodo the glass vial and says: "I give you the light of Eärendil, our most beloved star. May it be a light for you in dark places, when all other lights go out."
There you have him mentioned. And the reason is that he travels the sky in a ship, carrying one of the Silmarils (which are stones that magically shine) which is seen on earth as a star. The history of these things are very special to the elves.
As to why I identify with Eärendil is because one of the very first characters I role played was Elladan, who is one of the twin sons of Elrond, who happens to be the decendant of Eärendil. And finding a sigil for Elladan or Elrond is not possible, so I went with the first sigil I could find, and that belonged to Eärendil. So for years I've loved this symbol and now I use it as my signature.
The star in the center is a depiction of the silmaril and the dots in each corner are in many version a full moon at the top, and a circle around darkness at the bottom and a half moon on either side, to represent the year and travelling through the night constantly. So that's the image I chose for my signature (And actually had for my avatar until Joey made that for me as my secret santa. <3 you Joey Stark)