New jeans can be quite stiff and uncomfortable. The most natural way to make them feel softer is to simply wear them over and over again. However, if you'd like to speed up the softening process, follow the steps listed below.
Make sure you wash the jeans with fabric softener. In addition, be sure to wash your jeans each and every time you wear them. The more you wash them, the faster they'll wear out and become soft.
Use a small amount of laundry detergent when washing your jeans. If you use too much detergent, it may not fully rinse out of the fabric and will make the denim feel stiff and inflexible. Give jeans an extra rinse cycle to make sure all the detergent is washed away. Another trick is to add some salt to the water when you're doing a load of jeans.
Rub the denim with a piece of fine-grained sandpaper. This will not only soften the feeling of the denim, but will also create a worn, distressed appearance. Just be sure to evenly rub the entire pair of jeans to avoid patches of stiff denim.
Check labels when you're shopping for a new pair of jeans. Look for an indication that the jeans were subjected to enzyme washing before sale. Enzyme washing is a laundering process that some clothing manufacturers utilize to make jeans softer and more supple.
Wear the jeans as often as possible to help break them in.