If you got your piggies from a rescue centre they will usually help you to trim nails if you want to learn how to do it yourself. Some vet surgeries offer nurse clinics where they offer nail cutting, health checks etc. White nails are easier to trim as you can see the reddish pink "quick" ( vein supplying blood) running inside the nail and avoid snipping it! Dark nails are harder as you cannot see the quick as easily, and best to take a little bit off them if they are not too overgrown. Always find the best light source you can( by a window, under a lamp, get a helper to shine a torch on the foot) and keep the cutters away from the fleshy part of the foot itself.