I have friends and buyers whose does will be kindling litters soon, and I want them and their rabbits to have a smooth experience.
So, why do you want to be there when (or soon after) the kits are born?
The most important reason to be checking for the arrival of kits frequently is so that you can save kits born outside the nest box. In fact, being born outside the nesting box is the most common cause of death for kits who were born alive.
It is quite common to have one or more stillborn kits in the litter. (As a precaution, do not pick up your doe in the last week before kits are due.) The stillborn kits need to be removed immediately.
Next, you must make sure that the doe has cleaned her kits. So far, we have not seen any problems with the doe cleaning her kits. But if you happen to encounter this, try cleaning the kit with a warm, damp washcloth. If one or two kits have not been cleaned, and it looks like the doe isn't returning to them, it is possible that she thinks they are too weak to survive.
Then you want to make sure she has pulled enough wool to keep the kits warm. Some does, like Snowball, pull their wool far in advance. Some, like Tootsie, don't pull until they are kindling.
Finally, if it is cold, the kits have a better chance of survival if you bring them inside and only take them out to the doe for feeding. And make sure she feeds them.