Wood shavings is optimum bedding. Ideally Aspen, but coarse pine is ok also. NEVER cedar, and avoid fine pine.
Pour the shavings in, gently press down, and then make a dist and make a dent near a corner for the huddle to go in.
To clean, Line a bowl or tupper box with kitchen paper, or unscented kleenex, and place the chicks in there while you take the nest box, empty over the bin, scrape out (I find a scrap of cardboard makes a great tool for this), scrape all the poops off the corner and walls of the nest, then throw the cardoard scraper away, and refill the shavings.
When I have very young chicks, I just spot clean (pick up single poops as best I can) until they are a good few days old to avoid disrupting the nest too early. There´s always risk of the parents abandoning the nest, low but it happens, so it´s best to wait for chicks to be 5 days old before putting our hands in there unless absolultely necessary (makes for easier hand rearing should the worst happen).
Kitchen paper and newspaper are not acceptable nest bedding, They are things to use in emergencies (when finding injured pigeons etc). When we have the nest at home, those eggs didn´t incubate overnight, we had a few weeks to prepare and get the materials they need.
Inadequate bedding is the number one cause of spraddle leg (splayed legs), a life altering and easily avoidable condition.