A nose stud with a ball on the end refers to a nose bone, which is a straight piece of jewellery for the nostril with a small ball that rests inside the nostril to hold it in place. Because the hole in your nostril will shrink around the thin post of the nose stud as it heals, it makes the jewellery extremely hard to remove. The only way to keep the nose stud intact is to pull it through the piercing hole out from your nose, a process which will tear some of the healed skin around your piercing. Since you want to leave your skin intact, and since such jewellery is cheap and somewhat disposable, you will carefully snip the head of the nose stud off the surface of the nostril.
Warm your hands in soap and warm water and rinse them thoroughly. Soak a cotton ball in hot water and run it across the tin snips. Follow with a dry cotton ball. Dip a cotton ball in rubbing alcohol and sterilise the tips of the tin snips.
Dip a cotton ball in rubbing alcohol and swab down the surface of the nostril that contains the nose stud. Dip a Q-tip in rubbing alcohol and wipe primarily around the post.
Put on a pair of sterile rubber gloves. Gently insert your forefinger into the nostril so that it pushes lightly against the ball end of the nose stud. This will cause the outer end of the nose stud to move away from the surface of the skin, giving you more room to snip it.
Place the mouth of the tin snips on the outer end of the nose stud, as far from the skin as possible. Make a firm snip, cutting the end of the nose stud. Remove your finger from inside the nostril. Hold your hand under that nostril and tap the nostril gently. The other end of the stud will fall into your hand.