Q&A for How to Hem Jeans

Before you sew the hem, iron the fold so that it's perfectly flat and straight. For denim, it's also a good idea to hammer the fold so it's softer and easier to sew straight.

Before you hem your denim jeans, make sure they've been recently washed, soaked, and dried. Denim often shrinks in both width and length when it's clean, so doing this will ensure that the jeans aren't too short once you wash them. It's also helpful to iron the hem, then hammer it (yes, with an actual hammer) to the denim will be easier to sew.

If you are using a sewing machine, make sure you change the needle out to a denim or other heavy-duty needle. By doing this, you will ensure that the needle goes through the denim and does not break.

Yes, this technique will work on any type of jean cut for the most part. If you are taking up the hem a great deal, you may have some excess fabric inside the pants, but you should be able to flatten it out well enough.

You should use denim weight thread in both the top and bobbin threads. If you have different colors, the one that shows on the finished hem will be the bobbin thread if you are stitching with the wrong side up -- the inside of the pant leg is facing up and the hem is rolled to that side.

That sounds like a dart, not a hem. Consider going to an experienced tailor with this kind of complicated job.

You could hand sew a couple of support stitches at the top of the loop of excess (in the side seam would be the best place to hide them), or just cut it off.