Breast milk

How can I increase my milk supply? I'm due in 4 weeks and I want to breast feed my last baby, as I was unsuccessful with my first 2 pregnancies... I have tired mothers milk tea.... and some supplement pills (I forgot the name) but both didnt not increase my supply... the most I got was 2 oz from both breast combined 😞 Do you ladies have any tips that have worked for you? I want to be prepared this time since it will be my last. Oh yea I have breast implants... can that be a reason why my milk supply is low?