I'd thought I was well prepared for breastfeeding (reading, classes, watching friends etc) but there were some things I never heard beforehand which would have been really useful to know. I claim no expertise beyond my own experience of getting through the first six weeks of feeding :) but thought I'd share - and encourage others to do likewise - practical hints that I wished I'd known:
That "nose to nipple" is a good way to work out how far across your body the baby should be, but the chin should actually be closer to the breast than the nose when latching on.
That a good latch involves a mouth that's open wider than looks physically possible for a tiny baby's mouth!
That trying to visually check the latch during a feed a) tends to pull the nipple out and make the latch worse and b) can miss problems; how it feels is a far better guide to how it's going.
That for cradle/cross-cradle it's good to hold the baby's tummy in tightly to my body to help them feel secure - it also helps to tuck the lower arm out of the way below the body before bringing the baby in.
How to do sandwich and flipple/extended latch techniques.
That getting the baby's body into the right position before attempting to latch is more than half the battle - having help from another pair of hands can really help as you work this out!
That once the baby's in position you need to wait for a good gape and then move quickly to get the nipple in before it closes again.
That you shouldn't hold the back of the head or press the head against the nipple but instead bring the head close by supporting the side of the head (cradle) or neck (cross-cradle).
Hope this is helpful to someone!