Breastmilk production.

How do you ladies start up and even keep production? This is my second pregnancy but my 3rd child. My twins were 34 week preemies and never took to breastfeeding. I did pump however and I never got more than 3 ounces from each breast, I ended up completely losing all my supply just a few weeks after birth. I really want to breastfeed this baby but I guess I'm scared I won't have enough based off my previous experience. I'm only 9 weeks so I still have a long way to go, but I want to research all my options. Thank you in advance.