animation in pse is really easy, I broke it down into simple steps for someone else not too long ago. let me find you that post.

eta: here you go
QUOTE
to put a frame around the pictures you are animating what you do is merge all your layers down until you get to the frame (now frame layer). then merge everything after the frame down (now background layer). do NOT merge the picture. go about animating your pic the same way as normal then for each new layer the animation creates duplicate your frame layer and background layer. then arrange them so that your layers are like: background-animation1-frame, background-animation2-frame... then merge each set of three.
to make an object or something move, its basically the same. merge al layers above the object, and then merge all layers below, leaving the object by itself. then nudge or move your object a little at a time to create the animation. for each new movement you have to duplicate the object so if you want a bird to move right 15 space (nudges) I would have my original bird, duplicate it, nudge it right 5 times, duplicate it, nudge it right 5 more times, duplicate it, and nudge it right a final more 5 times. so it would now be three layers of birds. duplicate your layer that goes above and below the bird three times, arange like you did with the photo, then merge.
i hope that makes sense and helps! sorry i can't create screen shots at the moment.
(ps. you save as a GIF and select animate.)
and
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My tips for animation:
1. never merge layers until you are positive you have a copy of the layers, or that you won't need them again
2. nudge and count. when making something move count how many nudges you want it to move up/down/over and then for each layer that it moves in repeat that number of nudges so your animation moves smoothly. (I usually use 5-10 nudges depending on size)
3. variation. don't just have things move up and down or side to side. throw in some wiggling movements. as it moves side to side make it go up and down just a little. or vice versa. or make things glow/pulse/sparkle.
4. PATIENCE. animation tends to take a little bit of extra time, and it can get very headache-y. just have patience, and if you need to, save your work and take a break.
5. the maximum size for an animated siggy is 200k, which is larger than that for a non-animated one.