There are two ways that you can go about creating a GIF in Adobe Photoshop.  The first is to take a series of still images and put them together so that they are played sequentially to create the illusion of movement. The alternate way to go is to break a preexisting video into separate frames and adjust from there. With either method, the goal is to create a motion loop from a batch of individual frames.  Let’s see how it’s done:

1) Create Your Document

Choose the dimensions (in pixels) and resolution of your GIF.  You want to keep your file size as lowest as possible with GIFs, so a resolution of 150 with a maximum of 500 pixels for the height and width is recommended. Finally, since GIFS are made to be shown on screen, set your color mode to RGB.  

2) Import your images or video

To import a series of images, go to File > Scripts > Load Files into Stack and select the Browse button in the Load Layers window that pops up.  Select your images and then click “Open”. Photoshop will create a layer for each image uploaded which can be found in the layers panel in the bottom right hand corner. 

To import a video, go to File > Import > Video Frames to Layers.

3) Add layers into your Timeline

In your Timeline panel, click on “Create Frame Animation”.  Next, expand the Timeline flyout menu and select “Make Frames From Layers” to move all of your uploaded layers into your timeline. 

4) Set the looping cycle of the GIF

Have the looping cycle set to “Forever” like a traditional GIF, or limit to play only a certain number of times.  Click on the bottom left toolbar in the timeline panel to make these adjustments.

5) Export your GIF

Click File > Export > Save for Web (Legacy), name your file, save, and share!