Nail grooming is necessary and humane because most pets don't wear down their nails. Doing it once a month is a good rule. Not grooming nails regularly can cause the nails to grow so long that it is pain full for the dog to walk. And the nail can curve and in grow causing infection. Puppy's nails grow faster than adult dogs so they may need their nails trimmed more often.
Both cats and dogs tend to shy away from having their nails trimmed. There are some things you can do to make the task easier for you and for your pet. Make sure that you have nail trimmers that are not dull and that you are familiar with how they work. It is also important to know the anatomy of the claw, located in the nail is the quick which is where the nerves and blood vessels are. Do NOT cut this sensitive area. It's better to be cautious and cut too little of the nail rather than risk cutting this area. If you do accidentally cut the quick, any bleeding can be stopped with a styptic powder or stick. It's a good idea to keep it nearby while you trim.
Hold pet securely with one hand and clippers with the other hand.
Trim in one smooth stroke.
If nails are long, trim just a small amount and repeat in 10 days.
Avoid cutting off large amounts at any one time.
Always have styptic powder on hand in case of possible bleeding.
Remember to reward your pet when you are finished.