I wanted a pair of these Smocked Waist pants from Naartie Kids, but I thought, "I could totally make that for less".
In theory, they are no different than making a tiered skirt (tutorial here). You start with a pair of shorts then add two tiers, each wider than the last.
I made my pants out of jersey knit, so a rolled hem on my serger finished the edges. When you stitch jersey, the edges naturally ruffle up.
Shirred waist (elastic thread in the bobbin)
As you can see, I didn't quite achieve the capri length.
Love them anyway. And love saving money. I used a $3.00 fabric remnant to make these.