With my slings, I consentrate about two levels of accuracy. First is to be accurate enough to chase away a bear, wolf, dog,puma, lion or other big animal who will steal my food, dog, wife, sheep or whatewer, by hitting it, or close by it, repeatedly untill it retreats. Hopefully I am close to this now.
The other accuracy level is of course to be able to take out that little animal or bird who is supposed to be dinner.
Also included in this is that hit in a giants forehead we hear about

I propably need a little bit more practice before I am 100 % there yet

When aiming my sling at a target, I focus on it, point my front hand and toes toward it, rather like archery. I focus on where to hit, not to much on how, this just makes me confused. It is important to keep unimportant thoughts away.
Then it just is a question about consistent slinging tecnique.
It is best to practice as often as possible, for us beginners, unless we want to feel that we start at the beginning again each time

timann