If the nail is split it may not heal right and it is dangerous to clip it off depending on how far down into the nail it has broken. I would recommend giving him a dose of aspirin at a dosage rate of one adult aspirin for every 32 pounds or one baby aspirin for every 16 pounds twice daily at 12 hour intervals and this will help with the pain. You should also keep it lightly wrapped so he does not catch it on anything and injure it worse and also apply some antibiotic ointment to it before wrapping it. If the nail is far enough away from the nail bed you can gently clip it off but if it has broken low into the nail bed honestly it would be best to try and contact your local animal shelter as they have contact numbers for the low cost veterinarians in your area that could safely clip the nail off where it needs to be so it will grow back correctly and not to low as to cause injury or bleeding again.
shelter volunteer
14+ years of shelter work/ vaccinations/ disease/ illness/ injury/ medical care