Denim will shrink a bit the first time you wash it, so it is a good idea to do a pre-wash before hemming your jeans. This will help to ensure that you do not make the hem too short.Make sure to follow the instructions on the label for washing your jeans.
 It is important to change your sewing machine needle after every four hours of sewing or after finishing a major project to ensure that it is sharp enough to do the job. If you have not changed the needle in a while, then put in a new needle before you begin sewing the new hem., Denim and other bulky fabrics can be a bit harder to sew. They may get caught more easily, or not move as efficiently through the presser foot. To ensure that your stitches are even and straight, sew slowly.








Start by applying very light pressure on the pedal to get the stitches started and then only increase the speed slightly if the fabric seems to be moving along well.
If the fabric gets stuck, then you can always use the hand wheel to help move it along.
Wash the jeans first if they are new.
Use a new needle.
Go slow.
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