How do get a GIF to work in Photoshop?

i opened imageready and opened my animation.(260 frames)
i jumped to photoshop.
i opened my pic that i wanted to add the animation to.
now what?

What version of photoshop? Photoshop does not work with animation prior to CS3. That's why we have image ready for older versions.

CS2 has the capability of animations in Photoshop too.

Really?--Fair enough. Somehow I think the OP has moved on though. The question was vague to start with. I personally think Flash is the best program to use for animation or possibly some other high end software like After Effects.

When you are in image ready, make sure you are on the Last Frame )unless you want your new image to appear somewhere else in the animation, hit the 'duplicate frame' button, then switch into photoshop, open the pic you want in, drag that pic onto the other pic that is your gif, then switch back to imageready, and that new pic should now be appeared as the last frame, you then can duplicate frames, create tweens, or whatever you heart desires.
have fun.

-Sel