Housing/cages
I keep my rats in specially made hutches, I find these are the best type for me.
There are many different cages to choose from and what may suit one rat owner may not suit another. When pruchasing a cage think about the size; is it big enough for your rats, can you manouver it ok for cleaning etc. will it fit into the space you have designated in your house, how far are the bars spaced; if you have young rats they need a cage with small mesh or wire. Some cages have plastic bottoms which some rats like to chew (not all rats!). There are many places to buy cages from I would say have a good look around, you could end up saving yourself a bit of money too! Look on e-bay for cages, I've got some great bargains there!

Litter
Over the years I've tried lots of litters, I currently use Megazorb and cardboard squares (Ecobed), both of these are also used for horses.
There are many types that can be used, here are a few:- Bio-catolet, Bob Martins 100% paper recycled cat litter, Care Fresh, Yesterdays News,
good quality shavings.

Bedding
I use a shredded tissue type of bedding made by Petlife, there are lots of types that can be used like safebed, soft shredded paper, bits of cloth etc.

Cage accessories
All my rats have Rody igloos which they love. Hammocks are also good they love to lounge in them, tubes, tunnels, treat balls, laders, cardboard boxes are a favourite!

Food
I feed my rats on a rabbit based mix, details of the diet I feed my rats can be found here:-
www.shunamiterats.co.uk/diet.html
There is a fantastic book about rat nutrition which has recently become available, it is called The Scuttling Gourmet. It can be purchased from most rat clubs and from Acrorats site, I highly recommend it.
Always have water avialable for your rats to drink and give them fresh each day.