https://www.youtube.com/watch?v=id4U6iMwD9cSo Raul lopera Garcia is, essentially, Luis pons livermore's protege and successor in the menorcan slinging world.
Nice lad and one helluva good slinger.
My spanish sucks, but to be honest that really doesn't matter, the video is pretty self explanatory.
I skipped the talky bit at the beginning. Yhe interesting bit starts at about 4:20
And yes he does throw that well in competition
Some great looking slings he's made too.