The creation of a Horcrux eventually requires one to rip the soul apart. Then, a special spell is cast to infuse part of the ripped soul into an object, which becomes a Horcrux. As mentioned before, there is no limit to the number of Horcruxes a wizard can create. But somehow if he decides to create multiple Horcruxes, he loses more of his natural humanity and more likely he cannot die, unless all of the Horcruxes are destroyed properly. 

The ripping soul lingers around for a short period of time. You then have to bind your soul to theirs by casting a special spell. The process may be harmful and extremely painful especially when you try to split your soul apart for the first time. If you are not truly confident with yourself, you are not suggested to create a Horcrux. Consequently, under very specific conditions, a soul fragment can be sealed within an object without the intention or knowledge of the creator. While the object thus affected will, like any Horcrux, preserve the immortality of the creator, it does not become a dark object. Once you have your own Horcrux or Horcruxes, you are required to hide the object(s) in a place that no one will be able to find and destroy it, or else, you will become more vulnerable.