Cutting a nail that is too short is colloquially called “fast” because we call the nail bed, where nerves and blood vessels live, “fast”. So when you rush a dog, you damage its nerves and vessels and it hurts (a lot) and it bleeds (a lot). At the other end of the nail, where the nail meets the foot, the nail bed also adheres to the bone. The easiest and most effective way to stop dog nail bleeding is with a powder or a cosmetic pencil, which can be purchased at most major pet stores and pharmacies.
Fortunately, most of the time dogs don't try to lick their nails and rarely get infections from a toenail cut that's too short, but I understand that you want to be careful. In dogs with white or light nails, you can see the blood vessels and where they end, so it's easier to avoid the nail bed, but if your dog's nails are black or dark in color, it's harder to see them. Dogs that walk or run a lot on hard surfaces may not need to have their nails cut as often as dogs that exercise less often. Be sure to follow up any nail injury with something positive to avoid a negative association with nail cutting.
If your dog doesn't have the groove open, you should slowly trim it until you see a dark gray dot inside the nail. Many dogs can bite or bite due to sudden pain, which can undoubtedly make it difficult to cut their nails in the future. For the past three months I have bought all the recommended dog nail clippers, but I was petrified to use them on my dog. In this case, you'll have to trim your nails slightly every week or so so that they can be removed quickly and cut again.
Accidentally trimming a toenail that's too short is easy to do, but thankfully the risk of infection is low in most situations, so there's usually no need to take special precautions to control infections, such as antibiotics or aggressive scrubbing the nail. Standing and walking on toenails that are too long can change your dog's posture and gait, which can cause pain that could last longer than the temporary bite of a nail cut too short. On black dog nails, the only way to visualize how fast it is to carefully trim the nail until you see the pulp, which will turn gray. I was so scared for my dog that I couldn't be home when the hairdresser arrived, but apparently it caused one of the nails to bleed a little, not for long.