It is not uncommon to need to hem pants shorter than they were when purchased but sometimes this alteration can be intimidating when there is a cuff, or expensive if you pay someone else to do this. Let me tell you a little secret. Raising the hem on pants with a cuff can be done on the sewing machine without even having to do any hand stitches. (If you do not have a sewing machine you can do everything I am going to tell you about here without the sewing machine by using a needle and thread instead. The results will be the same.)
Supplies you need:
You will need the pants that are too long, chalk or pins to mark the desired length, pins to hold fabric in place while you press, a seam ripper, measuring tape or ruler, scissors, an iron, an ironing board, your sewing machine, thread that matches your pants. If you are going to hem without a sewing machine then you will need a needle and maybe a thimble instead of the sewing machine.
Step 1: Measure and Mark
The first step is to try on the pants and make a mark at the new desired hem length. The desired length was marked on this pair of pants with a pink glass-head pin. Look for it on the right leg, near the top of the photograph. This is the most important mark you will make on the pants as this will be the finished length.
Next, remove the hem stitches and any other stitches holding the cuff in place. The cuff may have a few stitches at the top of the cuff on the side seams. With your seam ripper cut these threads, being very careful not to cut the fabric. Next remove the stitches holding the hem. Fold down the cuff.
Now measure the length from the end of the original cuff to the very bottom if the pant leg. This is the fabric needed to recreate the same size cuff on your finished garment. In the photo above you can see the original length on the left and the fully extended fabric on the right. In this pair of pants it is about six inches. The white lines on the gray mat are one inch marks.
Find the desired hem length mark (pink glass top pen in this photo) and mark the length you just measured from the original hem to the bottom of the fabric. In this photo look for a pin without a glass top, just below the original length. This is your new cut mark. Before you cut the fabric, mark the length of the original cuff folds with chalk or a pin or both.
Step 2: Transfer Cuff Fold Marks and Cut Away Excess Fabric
Once your cuff fold marks have been made you can cut away the excess fabric. This cut is at the length needed to recreate the cuff. Anything longer than that is no longer needed and can be cut away. To do this I make a small snip through both sides of the fabric, then I insert one blade of the scissors into this snip so that I only cut through one layer at a time. To be sure this is straight and even, use your measuring tool and pins or chalk to mark where you need to cut at each seam and at the creases pressed into the front and back of the pant leg.
After you make the cut on the first leg you can use this leg to mark the cut line on the second pant leg. Go ahead and make this second cut now. It will be easier to see where to cut so that both pant legs are the same length.
Step 3: Press the Raw Edges Under
Press the newly cut raw edge under by the same amount that was originally used on the pants before you cut it away. On these pants it was about a half inch.
Step 4: Fold the Pant Legs Up to the New Top of Cuff Line
Once the raw edge has been pressed, fold the pants at the new top of the new cuff line.
Step 5: Pant Leg Ready to Press
Press the first pant leg along the new top of the cuff line. Once pressed use pins to hold this fold in place. Mark the fold line on the second leg, using the pressed edge from the first leg. Fold the second leg, press and pin into place.
If you are using a sewing machine, on the inside of the pant leg, sew along the edge where the new raw edge is folded under. If sewing by hand, using a hem stitch, sew the turned up edge to the pant fabric where it has been pinned in place. Sew this hem seam on both pant legs.
Step 6: Turn Up the Cuff
Turn the cuff up to the new desired hem length. In this photograph the white chalk line is the new desired length and the pins are marking where the hem was sewn to the pant leg. Fold the cuff at the new desired length mark. Press in place. Once pressed, tack the top of the cuff up by "stitching in the ditch". This just means sew a few stitches along the top edge of the cuff right on top of the seams in the pant leg. If you are using matching thread it will not show. Probably four or five stitches down and back are all you will need.
Step 7: Finished Cuff, Inside and Out
The first image above shows the finished cuff. The right is the view from the outside, the left has the pant leg opened up so you can see the inside, where the raw edge folded area was sewn to the pant leg.
The second photograph is the cuff after it was pressed up. The little bit of fabric at the bottom of these photographs is the portion that was cut away. You can throw away the little cut away scraps or you might want to save these cut away pieces in case you need to make a patch (wise if it is a child's garment). You can also see a stitch line in this second photograph across the top of the hem, about midway between the folds. This is the stitch marks from the original hem. Once this fabric is washed this will not show.