For some reason, I always have long introductions... so here is a TL;DR version:

I am a beginner, have only slung twice in my life, I've just made clay bullets and I'm from Western Australia.

Long Version:

I am a beginner, I've only got one crude sling that I made from string and a thin leather piece for the pouch. I've been meaning to get around to slinging for a few months, but never got into it until now. Angular stones suck... or maybe that's just me!

I have made twelve clay glandes that I hope to sling, with a variance between 20 and 98 grams by each individual projectile. The 20 gram one is a cylindrical ball that I added a small hole in the centre, to hopefully make it 'whistle', of course fine-tuning is probably necessary in order to get it to do that.

I have three cylindrical ones that weight about 28-29 grams each, and five biconical ones that weight about 40-80 grams each (With different levels of fatness), with four larger biconicals that are roughly 80-90 grams, and the biggest one that weights 98 grams (The GTFOH stone!).

They have not been baked yet, don't have a kiln and I cannot use fire... so I might use the oven.

But I'll probably just use tennis balls to sling around for a start. For one, Western Australian weapon rules are a little 'vague'... so better safe than sorry. I mean, what's to stop a police officer from saying "That's a Slingshot!" which are banned here.

But regardless, I'm going to sling no matter what! (Just hopefully when the cop's aren't around)

And If you've managed to go through all that, thank you. Hopefully my comments aren't all this big. 

Welcome!

Greetings Jackinati, I think we all started with a string and leather sling and it does the job well enough. Tennis balls are the way to go while learning the ropes, and I'm glad you are concerned with others safety including your own. It is possible to "brain" yourself!!! ( I have seen it, long story...) Anyways, welcome.