Am going to go against the grain here and say don't worry till after. I got by with the little sachets that the midwives gave me as well as some breast milk which also does a good job. You only need a teeny bit otherwise you risk worsening the latch because the nipple is too slippery.
I do accept that Lansinoh is seen as the cure all of sore nipples and I'm not denying it is effective but sometimes I think if we concentrated on getting the latch correct to start with, it would prevent lots of problems.
PS : other nipple creams do exist, some women are allergic to lanolin. 