Wanting to conceive twins!!

My partner and I want 2 more kids however would like to do it at the one time due to personal issues, age etc. I was wondering if there is anything i could do to increase my chances of having twins.

Ive been told to take double dose of folic acid as it apparently increases ovulation to release 2 eggs. Ive been taking a normal dose of folic acid anyway along with pre conception vitamins.

I dont have any trouble falling pregnant, i would just like to increase my chances. I know heaps of people who have fallen pregnant on clomid however i dont actually need it as i dont have any fertility issues, so wouldnt be able to have it prescribed to me by a doctor.

Does anyone know where else i could get clomid from? Im in Australia so not sure if its possible to buy online? I do have soy isoflavones as have been told they are a natural alternative to clomid, so i might use that this month and see how we go.