I love animated GIFs. I make them whenever I can (thegifthatkeepsongiving.tumblr.com). There are tons of apps and different ways to make them but this is how I do it.
First off, and most importantly, it’s pronounced with a hard G —like gift without the T. No matter what anybody else tells you, its GIF. Thanks, Obama!
Find the video you want to make a GIF of. I really like making Hugh Grant GIFs, so I’ll use a screen-capture software like Quicktime to grab clips without having to download the movie.
Select File > Import Video Frames to Layers
From here, you can import the entire clip or a selected range. GIFs that have seamless loops work the best.
Now, you can make adjustments like you would any other Photoshop project.
Select File > Save for Web
This is the Save for Web setting. You can most likely keep everything default. Make sure you are saving as a GIF (pink arrow) and that you are looping forever (green arrow), because GIFs that don’t loop forever are zzzzzzzz. The goal is to keep your file size under 5mb (orange arrow) or 3mb if you plan on using a lot of GIFs on one page.
If your GIF is too big, you can try making the image smaller by changing the image size or reducing it by a percentage.
Save and you’re done!