You can prepare your frames in advance, if you like, in another program such as Adobe Illustrator. Then, import the frames (source files) into Photoshop by going to File > Load Layers. Choose two or more files to load into an image stack, add all the frames, and press OK.
With your Photoshop layers open, go to Window > Timeline and click Create Frame Animation.
Select Make Frames From Layers from the menu in the right corner of the Timeline panel. This will allow you to take your layers and separate them into frames within the window.
Set your GIF to Loop by clicking the repeat menu. Within the Timeline you can adjust how long each individual frame is on screen and decide how long the GIF should loop. (Most GIFs will loop at the Forever setting.)
Once you’re happy with your animated GIF, export it by selecting File > Export > Save for Web (Legacy). Then make sure you save it as a GIF in the proper folder.
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