The first week or two I put down newspaper with paper towels on top of that. Then I switched to wood shavings. It's easier for newborns to find the new granual food you put down on the paper towels. I place food all around the food bowl on the paper towels and in the bowl for them. It's a fun treat to watch them after 2 weeks recieve the new wood chips. They enjoy scratching and showing off in them. It's like every body now has a new job to search for bugs, scratch, dig, peck,,,even though they never find anything,,,they sure like to hunt.
Everynow and then a moskito hawk will fly into my red light and boy oh boy what fun that is! I pity the fool moskito who dares to come into my brood pen! It is a sight to behold! If you can catch one for your 2-3-4 week old chickens,,,try it and place one in their pen. It gets real intense as the thing lands on the ground. All chickens hover staring until someone strikes it,,,snatches it up and makes a couple of circles around the brood pen running and chirping with all other chickens following and chirping behind. It's the big prize,,the trophie,,,the skeeter of all skeeters and everyone wants it bad!!! Finally, the prize winner will swallow it and the excitement is over. It is so much fun to watch. Amazing how they instinctively know this so young without a moma hen at my house to show them. I showed my husband and daughter and they both laughed!
Good luck with your babies!