Making a GIF/PNG Transparent In the Gimp

I have to search on the Internet for the solution to this problem every time I need to make the background of a GIF disappear, since it’s quite a strange process. So here is the short recipe:

1. After the image is loaded, you need to add an Alpha channel. Go to Right Mouse -> Layer -> Transparency -> Add Alpha Channel. Nothing wil seem to have happened
2. Perform any kind of selection on the image
3. Hit Ctrl-K, or Right Mouse -> Edit -> Clear
4. Continue until the checkered background fills the area you want transparent. Hint: if you want to get rid of single pixels, just enlarge the image and use the rectangle selector
5. Save in a format that supports transparency, like GIF or PNG

That’s it!