Conditioning a training marker
Some people would like to argue that the use of a clicker for training a guinea pig is not necessary. However, using a clicker or any other training marker (anything that "marks" the moment the animal did something right) can speed up learning and create an environment where the guinea pig is volunteering good behavior and being an active participant in the learning process.
Conditioning your guinea pig to a marker is very easy. You can use a clicker. I recommend Karen Pryor's i-clicks because they have a softer, quieter click than most other clickers. You can also use a marker word such as "yes" or "yep" or "good" instead of a clicker.
First, see if your guinea pig will easily and eagerly take small treats from your hands. The treats should be easy and quick for them to eat. I normally use small pieces of carrot, lettuce (not iceberg), bell pepper, and any of their regular vegetables from their daily salad. If she will, then you're ready to start training!
1. Click and treat a few times to get the guinea pig used to the idea that click = treat. This step is just to get her used to the sound of the clicker and to gauge if you'll need to muffle the clicker or use a different marker entirely. If she's comfortable with the clicker's sound, move on to step 2.
2. Watch her for any movement and give a click and a treat. Don't try to be picky. You are basically trying to make her believe that holding still = no treats and that moving = treats. Move to step 3 once you see her anticipating her treat after the click.
3. Now, you'll start to use the conditioned clicker to start training a simple behavior such as targeting or hopping onto a platform or an easy trick like spin.
Conditioning the clicker shouldn't be a long process and should just be a small part of the overall training process, as the most important connection that your guinea pig makes in regard to clicker training isn't "click=treats" but rather, "I can make clicks happen by doing stuff." The length of time it takes your guinea pig to reach this conclusion is NOT indicative of her intelligence, but is simply related to her temperament.
