Keep no formula in the house
Work with a Lactation Consultant
take a breast feeding class
No paci or bottles for 6-8 weeks
Its going to be hard at first but once you get over that hump and into a schedule its sooo worth it.
Trust your body
but with my daughter I did stuff like watched video after video until I found one with a woman whose chest was like mine -- helped out IMMENSELY with latching
drink lots of water and stay hydrated
eat a good diet and don't 'skip out' on calories (you'll need some extra)
don't think "I"m not producing enough!" just because your LO likes to nurse nad nurse and nurse. Cluster feeding and extended nursing times is a GOOD thing because it helps to establish/maintain your supply.
don't let anyone tell you 'he/she is too old'...breastfeed as long as you feel necessary/comfortable with
DON"T buy 'backup formula' because it's too tempting.
get a good breastpump and use it.
figure out what kind of 'eater' your LO is (mine was a 'napper', she'd take power naps between breasts) so whenever he/she is done, pump to empty your breasts. Doesn't matter how much you get, just get it out to help max out your supply
be proud of yourself that not only did you MAKE that gorgeous little person, but you are the SOLE provider of EVERYTHING he/she needs! Huge ego boost for me really kept me going in the face of a LOT of negativity about breastfeeding my son.