when my baby was born prematurely, i met with the lactation consultant at the hospital frequently. i would have her paged when i arrived to visit my daughter (that was the system at the hospital we were at) and she would come and guide me hands on to try to bf my dd. i would ask her any questions about pumping at that time she would work with me on position and latching. she wasn't able to latch on for quite awhile, but we just kept practicing. i used a hospital grade pump and we gave her bf in a bottle. there are other options like tubing and finger feedings. but what we did was 1) put to breast, give best effort to latch her on, if not latched at least let her suckle a little 2) then give a bottle of previously expressed breastmilk 3) tube feed if she wouldn't take the bottle 4)then burp and put down asleep 5) pump milk. this was our routine. i wasn't able to room at the hospital, they were full. so i wasn't there for every feeding, but i pumped at home and brought my stash with me to the hospital and they stored it and used it when i wasn't there. my daughter was sent home from the intensive care after one week. after that i made appointments to see a lactation consultant at the medical center weekly. then she latched on, right around her due date, six weeks later! and i ditched the pumps and bottles. and just nursed exlusively on demand. forgot about the schedule and everything. now she won't quit

she is 2 yrs and 4 months old now! i have another friend whose child never did get the hang of it and she pumped and gave BM in a bottle for a year! although she did later say that she didn't get as much help with latching and positioning and just kind of gave up on getting her to the breast pretty quickly and stopped putting her to the breast. she just pumped and gave it in a bottle. oh and my dd like a lot of preemies had a very difficult time regulating sleeping and eating. so i did have to rouse her to eat, because she wouldn't otherwise during the first 6 weeks. then after that she would get so overstimulated so easily, that she couldn't fall asleep and stay asleep. i used the pregnancy pillow to support me on my side so i could just lie on my side all night comfortably with her tummy to tummy with me and nursing on and off all night. she had to be tummy to tummy. this worked to regulate her and eventually she developed more normal sleep cycles. preemies sleep patterns do not follow full term babies sleep patterns and this was frustrating because i couldn't find this issue addressed anywhere for quite awhile. i found out that preemies spend very little time in deep sleep compared with full term babies (who don't spend that much time in deep sleep either) but preemies spend even less time in deep sleep. it is a survival mechanism. they spend most of their time in light sleep and are very sensitive to stimulus. except in the very beginning when they might be completely shut down and in a very deep sleep as a defense mechanism to shut out all the stimulus.
also i actually found it a bit frustrating to get bf advice from some of the traditional sources of support because bf moms with full term babies just don't understand the extra challenges of bfing a preterm baby. it is important to read books about preemies, not just regular parenting books, and talk with other parents of preemies and talk to the specialists. there are some special issues with preemies. and of course every child is different. so there are individual differences as well.