Nail biting is a bad habit; there are methods to learn to stop biting your nails, with a little willpower
Many people have the nasty habit of biting their nails. It is often an unconscious and repeated habit, other times it is a sort of tic, which is activated only in periods of particular boredom or stress. There are some methods to stop nail-biting, very useful for the health of the hands and mouth, and also for social life: nibbling the nails in public is often considered a rude and disrespectful gesture.
Before thinking of a method to stop biting your nails, try to understand why you do it: if it's a question of boredom or stress, you can try to limit the use of this habit with countermeasures. For example, carrying around an object to be manipulated when you want, like a small pin or an elastic band, can be of great benefit: while handling this small object, it does not even occur to leave it to bite your nails. Even chewing a candy allows you to get the same relaxing stimulus, without ruining the manicure.
Many women stop biting their nails when they have beautiful and cared for, or even covered with nail polish or nail art: a well-groomed hand, with a regularly done manicure, tends to invite the owner to keep it that way. So try going to the manicure regularly, once a month. When, however, the use of nibbling is regular it is necessary to counter it with some slightly more "invasive" methods. For example, you can cover your fingertips with patches; in this way it is impossible to reach the nails and indulge in one's own bad habit. The patches can be replaced frequently and the fingers will be preserved.
Of course, you can't always stay with your nails nailed down, when you remove the covers, for an important occasion or for other reasons, you can apply a particular glaze with a very bitter taste, which works like a behavioral conditioning: every time you try to biting the bitter taste leads us to desist. If you have good will power you can try to preserve one finger at a time, maybe for a week; usually when one compares the finger "safe" with the other neighbors, one tends to stop with this bad habit, because the unsweetened fingers are beautiful and pleasant.