I found this link while attempting to do my first hem on a pair of jeans (on sale at Gap Maternity...8L... much too long).
How to Hem Jeans
I'm quoting the tutorial here as well... This is an easy way to make a perfect hem... it looks great and the few mistakes I made were because I've only sewn like ten things in my entire life...
I found this fabulously perfect way to hem jeans on the Cavaricci site, which has since been taken down, so here’s the lowdown. This method keeps the original hem in tact and is especially helpful now that all jeans are made to be 34 inches long for mammoth supermodels. Plus, it took less than 30 minutes.
A couple notes: It’s best to do one leg at a time, so as not to have too much undoing to do in case something goes awry. Also, it’s good to know the length that you want each leg to be. Sometimes, one leg will be a bit shorter or longer than the other before you hem.
Step 1: Decide how much length you would like to take off. Divide that number in half. (Hems should fall just below the bottom of your ankle. Also, if you generally wear high heels, or a certain height of heel, you might want your hem a bit longer – it should fall an inch to a half inch above the floor at your heel.)
Step 2: Cuff the jeans. I wanted to take two inches off my hem, so I measured one inch out from the original hem line and pinned. (Do not include the distance from the hem to the end of the jean in your calculations.)
Step 3: Pin around the rest of the cuff, taking care to measure each time you pin.
Mind the seams while you’re pinning. Make sure that the stitching lines up at each seam.
Step 4: It’s time to stitch. You want to place your needle and continue sewing right next to the original hem. Stitch on the right side of the hem, or the side farthest from the bottom of the jean. Sew all the way around the cuff. Be sure you don’t sew through both front and back sides of the jeans (making it so that the foot hole is sewn shut)!
You can either cut the excess off, leaving about a half inch for fraying, or iron the extra material in.
Turn the leg right side out and press the new seam flat, revealing the old hem.
Voila! No more slouchy, unflattering leg.
Updates: I’m glad everyone has found this tutorial useful. I wanted to answer some questions here that continue to arise. If you are still having trouble, just leave a comment; I usually respond within a few days.
1) Yes, this trick works just as well with jean skirts, good point!
2) If you have already cut your hem off and still have it, no worries. You can still follow these directions. After you have decided on a length, do not divide in half as Step 1 suggests. Move on to Step 2. You will essentially be reattaching the original hem in this step. Pin the stiched line at your desired length (for instance, if you want your jeans to be 30 inches long, measure 30 inches from the inseam and pin the disconnected hem to that length on the jean leg, right sides together) and follow the steps from here. If you have already thrown away the hem I am sorry to say you’ll have to try and recreate the look from scratch.
3) If the jeans leg is flared, cut off the hem about an inch above the stitched hemline. Measure the circumference of the hem. Then, measure the circumference of the jean and the desired length you’re hemming it. Open the side seam of the jean several inches above where you want the jean to be hemmed. Take in the jean to the same circumference as the hem. You’ll want to make this look gradual. Reattach the hem portion following the directions in No. 2 above. I wouldn’t recommend using this method if the jean leg is more than an 1 1/2″ larger than the circumference of the hem.
4) This method can easily be done without a sewing machine. Follow the directions, just use your hands, needle, and thread.
5) If you are having trouble sewing over the seam with your machine, try a thicker needle. If this fails, you can always sew up to each side the seam (be sure to backstitch) and sew over the seam by hand. It works just as well. Also, a zipper foot may help.
6) I hang dry my jeans and tuck the excess fabric at the bottom up before hanging them, so I don’t need to iron the bottom flap each time. Alternatives to this, would be to use some Stichwitchery (a bonding, iron-on product) to adhere the excess material to the inside of the jean. Or, you could cut the excess off to 1/2 an inch and apply Fray-Chek a glue that keeps the material from unraveling.
Thanks for stopping by and happy hemming! -Dacia"