The Guinea Pig needs a special kind of cage, the ideal one being one with a plastic tray on the bottom and bars as walls. The plastic tray is easy to clean and you can easily change the bed.
You should know that the wood bottom cages are not recommended because the wood retains the pet’s urine and creates a fowl smell.
The aquarium type glass cage is not suitable either, because the little pet will be sound proof isolated and it will become scared and edgy.
Also you must not make the cage yourself out of dangerous or toxic materials because the little guinea pig tends to nibble on everything around it.
There is even a better option than the cage and that is the open enclosure through which you can interact with your little pet at any time. Still make sure that the walls are tall enough so the little one will not escape by climbing them.
The guinea pig needs enough to run but it will feel fine if you introduce inside the cage a few ramps and little ladders that will allow it to run and have fun.
Keep in mind not to place them too high above the base of the cage because the little guinea pig could get hurt if he falls from height.