Hello everyone
Greetings to you all in this community 
In making our outfit, we have different types of slit like a straight slit, inverted and pleated slit like this, it depends on ones choice or preference, today I will show you how I made this pleat to a short gown, pleated slit can either be cut together with the back pattern or inserted after sewing the back pattern together just as I made this. The cutting and sewing process will be explained below.
Cutting and sewing process of a pleated back slit Short gown
First was to cut out the front and back bodice of the lower part of the gown with the measurement taken
The front and back were sewn together with lining which was used to turn it inside out for neat finishing.
The back bodice were sewn together with the dart sewn inward and the zipper allowance was left open while I left 10" from the hem for the slit
To make the pleated slit, I cut out 12 x 15" which was cut to align with the pattern on the fabric
It was taken to the sewing machine and I hemmed it then sew it to both sides of the slit, the excess were then pleated where the slit started from
This is how it looks when turned to the right side
The front part of the Lower bodice was sewn to the back bodice and was set aside, now your desired upper bodice can be sewn to the lower part to make a complete outfit
This is so easy and comfortable to wear and walk with as the pleat will prevent the tight from being visible for those that don't like some part of their body to be seen, the pleat also serves as a beautiful design to the outfit.
I hope you like the beautiful outcome of the design of pleat I made, just as I love it.