Write an article based on this summary:

Select a pair of nail clippers. Purchase styptic powder or corn starch, if you do not have them already. Select a hand towel. Prepare the area where you will trim your guinea pig's nails.
Baby or animal nail clippers will work, so you could use either type. Keep in mind, however, that human clippers squeeze the nail together before clipping it; this may be painful to your guinea pig.  Animal clippers are guillotine-style, ensuring that the nail won't be squeezed. Also, they open more widely than human clippers, which makes the nails easier to trim. You can find this type of clipper at your local pet store.  You can try both types of clippers to see what your guinea pig is most comfortable with. Make sure to be careful of the quick. The quick is the reddish part at the base of the toenail. Try not to cut into it, as this will cause your guinea pig to bleed. If you can't see the quick, try holding a flashlight up to the nail when you cut it or only cut the tip-off. These substances will quickly stop the bleeding if you trim the nails down too far. They are equally effective at stopping the bleeding, so you can use either one.   Styptic powder can usually be found with men's shaving products at your local grocery store or pharmacy. Cornstarch is located with the baking products. In case your guinea pig is squiggly during nail trims, you can wrap him/her up in the towel to restrain him/her more easily. If you have previously used a towel to trim his/her nails, keep using the same towel each time. This will help to keep the process more consistent. Plus, he/she may feel more comfortable with one towel over another. Organizing everything that will you need for the nail trimming ahead of time will help the process go more smoothly.  Place a small towel, nail clippers, and styptic powder (or cornstarch) on a counter or tabletop. Placing a small amount (about 1/4 teaspoon) of styptic powder or cornstarch on a paper towel ensure that you have quick access to these substances if you need to stop a nail from bleeding.