Put the pants on and fold the cuff of the pants to however short you would like them to be. Hold the fold in place with 1 or 2 pins and remove the pants. If you want, put on something else. Or not.
Step 1: Measure Original Hem
Measure from the original hem line to the bottom of the pants. We'll call this measurement A.
Now add 1/4". We'll call that measurement B.
In the photo, the original hem line to the bottom of the pants was 1/2". So A=1/2.
1/2 + 1/4 = 3/4 inches for measurement B.
Step 2: Measure How Much You Will Inevitably End Up Chopping Off
Measure from the bottom of the pant leg to the fold you created in Step 1. Take that number and subtract Measurement B. We'll call this Measurement C, a.k.a. The amount that gets chopped.
I measured from the bottom of the pant leg to the fold and got 6.5". 6.5 - 1.25 = 5.25" that will get chopped.
Step 3: Measure for the Chopping
Take your Measurement C and measure that many inches from the bottom of the pant leg. Fold it over and pin it in place. Be fairly exact about this step. This is the step where if you are cutting bootleg pants or skinny jeans, things may get a little funky. The fabric may have folds and may not lay flat. However, it may not be that big of an issue depending on how much fabric you are cutting off.
My measurement was 5.25, so I measured 5.25" up from the bottom, folded it over, and pinned in place.
Step 4: Cut It Off!!!
Cut along the fold. Unpin the excess material and discard.
Step 5: New Hem--First Fold
Take Measurement A and measure that many inches up from the bottom of the pant leg. Fold towards the inside and pin in place. I found it helpful to put the pins on the outside of the pant leg for the next step.
My Measurement A was 1/2", so I folded over 1/2" to the inside of the pant leg.
Step 6: New Hem--Second Fold
Now take Measurement B and fold over the bottom of the pant leg again towards the inside that many inches. Pin in place.
My measurement B was 3/4", so I folded it over 3/4".
Step 7: Sew That $h¡t Up!!!!!
This is where the "add a 1/4 inch" from Step 2, Measurement B comes in. Seam Allowance!!!!! Sew it all up, using a 1/4" seam allowance.
My seam allowance is on the left side of the machine foot in the picture.
Step 8: Make Sure You've Got It All Correct
Measure from your newly sewn line to the new bottom of your pants. It should be the same (or relatively close) to your original Measurement A. If not, there is always hope for capris.