Found this on Wikipedia, hope it helps a little
Most of the time the cartilage itself is not pierced, but the small gap between the cartilage and the bottom of the nose, typically at 14ga (1.6mm) although it is often stretched to a larger gauge. The nose has many nerves running through it and nose piercings can be painful, but it varies by individual. This piercing heals within a month and a half to three months also depending on the individual. Stretching to a larger gauge should never hurt with this or any other piercing. It should only be stretched by 1mm at a time and it is advised to wait at least a month between stretches. If you go past a certain point, usually about 8mm, the cartilage gets forced towards the top of the nose, which can be uncomfortable.
Another option is a septum retainer, which is staple shaped. This type of nose piercing is particularly easy to hide when desired, for example to comply with a dress code. A septum retainer makes it possible to turn the jewelry up into the nose, concealing it. With black jewelery flipped up into the nostrils, this piercing can be made practically invisible. A normal septum piercing can also be hidden by pushing it to the back in to your nose , but it may be uncomfortable.
