A proper house is needed for a Cavie to live and play. It should have an area of 1.4 sq. ft. for one or two animals and at least eight (8) inches tall.
The cage must have a solid bottom and plenty of ventilation for air. They also need clean, dry bedding in the bottom of the bottom of their cage. The best bedding are alfalfa, timothy, or clover hay which they can also chew on.
But the amount of alfalfa hay must be controlled and not to be given on a regular basis. Only give alfalfa hay once a week or fortnightly. Timothy hay can be given regularly and they help to clear the digestive system of piggies.
Try not to use cedar bedding because it wreaks havoc on their lungs. The bedding should be changed at least once every three days to keep them from laying in their own mess. You may want to add a block of pine or ash wood for your Guinea Pigs to chew on. They also like hiding boxes to sleep in.
Finally, it is good to have a dish to put their food into instead of spreading it all over the cage.
All the best to you & your pet!