Photoshop CC 2017 tutorial showing how to create GIF animations from videos, graphics & photos! NOTE: Steve Wilhite, the inventor of the GIF, stated in 2013 that "GIF" is pronounced with a soft "G", ...

You can start on the Canva website and click on the video. Choosing the correct size is important here and it really depends on where you plan on posting the video. You can also choose a custom size.