I know after they have drink milk, you use a warm clothe and gently wiped the stomach area. If use bottle feed is hard, can use syringe too.
If I am not wrong, they need to be fed 3-4 times a day. It does not need to be bathed first cause it's too young. You can however, use a warm cloth to wipe them.
In the nesting box, you put some clothe and if can, a hot tumbler and just slid in beneath the clothed to make it warm.
Here's some info which I search out and I hope it can help you.
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http://www.wikihow.com/Feed-a-Newborn-Kitten
=http://www.kittens-lair.net/raising-a-cat/orphan-kittens-nutrition.html
Hope it helps!