The leather of a Tignanello handbag makes it an expensive status symbol. It should not attract dirt, but when it does the handbag has to be cleaned immediately. Like any other leather product, a bag properly cared for will last for many years.
The Tignanello website suggests using a high-quality leather waterproofing spray to make the leather less prone to absorb dirt, grime and stains. This may change the feel of the leather a bit but will not damage the product. Test the spray in a small and inconspicuous area of the bag before applying it to the entire bag.
Use a slightly damp soft cloth to wipe off surface dirt, and a clean cloth or sponge to eliminate recent spills. Never put the bag in water or expose it to a chemical product. However, if the spill is significant, wipe the leather with lukewarm water and let the bag air dry.
Use clear saddle soap or leather cream to remove deep spots from the handbag. The website says any product like this can temporarily darken the leather, but the color will return when the bag dies. Use this as a last resort.
Avoid exposing the bag to adverse weather conditions and extreme temperatures. A bag caught in the rain must be dried with a cloth or left to air dry. Never leave the bag near a heat source, which could dry out and discolor the leather.
Never let the bag near grease, oil or ink. All three could leave permanent marks. Leather cream may cover some light marks, but it's not likely. Use an eraser to remove pencil marks on the bag.