i would reccomend AGAINST sawdust buttons are prone to getting poo stuck on there feet and its very difficult and stressing no them when you try getting it off often times resulting in a broken toe or taking a bit of toe right off as it requires pliers to break it off you can easily pull toe tips off useing jsut your fingers gently i have sadly done this trying to be as gentle as i could running the toe under warm water for a long tiem working at it still removing the toe tip :(
if you want somthing cheap to use for bedding try alfalfa pellets (rabbit food) you can buy a 50 pound bag for cheap and it smells good and doesnt get glued to the feet.
as for young chicks from hatching to about 2 weeks use those foam like drawer liners that grip and just change them or wash them once they get really dirty ive also heard of people useing towels(with no string edging) and jsut replace them and wash them when they are too dirty. once they are larger however and the cage is getting noticeably smelly or dirty after only a few days you can use bedding.
i wouldnt reccomend sand box to little chicks as they could mistaken it for food and try eating it causeing a blockage and they really wont attempt dust bathing untill about 3 weeks of age anyways.
newly hatched chicks till around 4 weeks eat gamebird crumble ground up to the consistancy of corn meal (very fine powder)
it pays to invest in a single serve coffee grinder as young chicks will eat ALOT much more then adults!
also its a BAD diea to wet or moisten any food its fine dry.
after about 4 weeks they should be large enough to handle normal gamebird crumble unground
also for young chicks you also need to grind up the oyster shell to a find dust too or cuttle bones or whatever else you use as a calcium sorce.
your also gonna want to be sure youve got a screen or mesh tight fittnig lid before the chicks are two weeks at about two weeks is when they begin testing out there wings i recently lost one of my 2 week old chicks when it escaped and was eaten by my cat.
for water you can use a jar lid and some marbels to ensure they cannot drown newly hatched chicks will often times sleep where they fall and sometimes thats in the water dish!
if youve got any more questions feel free to ask