It's FOSS published a tutorial about making GIFs and animated banners in GIMP.

How to Make a GIF in GIMP [Simple Tutorial] - It's FOSS

You can use the powerful and versatile open-source image editor GIMP to make gifs and animated banners. This simple tutorial shows how to do that.

How to Make a GIF in GIMP [Simple Tutorial] - It's FOSS