Having now breastfed three kiddos from birth w/the first one having to be taught suck/swallow because she was so premature, here are some tips I've learned:
Relax, relax, relax. The baby will be hungry and screaming and you will feel your biology kick in and you will start to panic. Take a deep breath and make sure that you have a good latch and good position, this way you will be less likely to have to unlatch baby to move around. However, do not hesitate to unlatch baby if they are not latched properly or if you are in pain.
If something happens to your nipple and it gets cracked or gets a sore, it will heal! I promise. Try to change the latch and positioning and get it feeling better. Don't give up. It doesn't feel so nice when it is healing, but IT WILL HEAL, so just keep going through it and know that the week or so of discomfort will go away.
Try and nurse in all sorts of positions. My DD#2 had some terrible habits and was preferring one breast to the exclusivity of the other and so I used a football hold on the side she didn't like and all of a sudden she'd nurse there again. Don't be afraid to experiment! Lay down, sit up, football hold, across the body hold....do it all!!!
I also second the pulling the baby in suggestion. When you are holding your breast and holding the baby, pull them in until you feel as though you are suffocating the baby. You won't really be (just make sure you watch their nose and make sure it is getting some airflow) but it does feel a bit strange.
Make sure the baby's mouth is WIDE open before you stick your breast in there. You want to make sure they are holding as much of the areola in their mouth as they possibly can, this really will make things MUCH more comfortable.
I'm sure there's more and as I think of them, I'll add......
And, oh yeah, GET HELP! Find a lactation consultant, LLL, or experienced pal to help you. Find someone you connect with, who is not going to irritate you or put you down. Don't hesitate to call around, someone who's been there before is an invaluable resource!!
One more, don't get discouraged. You've never done this before and neither has your baby. There is a little bit of learning (okay, a lot) that needs to happen. Even if this isn't your first nursling, you've never nursed THIS nursling before and that makes it a new situation. Go easy on yourself and enjoy the ride!!!!!