Yes, you can trim them with clippers. Just be careful to only trim the black ends right on the tip. I kind of run the trimmers along the back of the nail moving forward toward the tip until it seems to catch. That's usually where the nail tip meets the base and where it can be cut safely. I usually keep a tin of cornstarch on hand in case I nick the nail and it bleeds a little (I've never had to use it - it's just a precaution). I've also used emery boards to file the nails down a little bit if I want them to have a little bit of climbing traction left.