Ideally you shoud wash your jeans as little as possible to keep their original colour and get patina naturally (at each wash the colour becomes less intense and the weave shows through).
When the time comes to wash your jeans:
empty your pockets.
turn the jeans inside out.
put them in the washing machine without overfilling it to allow water to circulate and prevent creasing.
wash at 30° because the colour/fading contrast is accentuated by the washing temperature.
choose a liquid detergent.
select a short spin to avoid the appearance of white lines on the fabric.
take the jeans out of the washing machine as soon as the washing cycle is finished to avoid permanent creases.
hang the jeans up to dry naturally in the air (do not use a tumble dryer as it damages elastane).
Understanding the care label:
The first symbol is a washtub (representing your washing machine) and the number inside shows the maximum temperature you should use to wash your trousers. This symbol is underlined if the
use of the tumble drier should be limited. If the symbol is crossed out, the garment should not be washed but can be dry cleaned.
The fourth symbol, a triangle, concerns the use of bleach. If the triangle is crossed out, do not use bleach.
The iron symbol uses a dot system to indicate the maximum temperature to use when ironing to avoid burning your jeans or harming the elastane. One dot is for a cool iron, two dots for a warm iron and three dots for a hot iron.
The second symbol indicates whether dry cleaning is advisable and is used by the dry cleaner to know which product can safely be used.
The last symbol explains how to dry your jeans. A dot system shows which heat setting to use. One dot is for a low heat setting and two dots are for a high heat setting. If the symbol is crossed out the garment shoud be not be hung up to dry on a clothes hanger.
By observing these simple rules your jeans will never shrink and will stay comfortable as long as possible.