Guinea pigs need plenty of exercise and in order to keep your pet fit and healthy you should ensure they get some time out of their hutch each day. You can purchase exercise areas suitable for small pets and these can be easily put up indoors or outside. If you are going to put up an exercise area for your guinea pig outside, only do it when the weather is good, only site it on untreated grass (no pesticides or fertilizers), and you MUST always be present to watch for predators.
Guinea Pigs can be litter trained but it is not always easy and some just don't take to it at all. There are various different methods of litter training guinea pigs, but which ever one you try it is important to remember to be consistent and reward your guinea pig with a small vegetable treat when they do well.
One method of litter training your guinea pig is to place a litter tray in the corner of their hutch and add some soiled shavings. This will encourage them to use the litter tray.
Guinea Pigs can be taught simple command training such as coming when they are called. Keep your commands constant and reward your guinea pig when they respond.