Before you start, take measurements of your waist, chest, shoulders and length. Now start cutting a piece of fabric with the following measurements in order to create the skirt.
The width of the top should be 5 inches larger than your original waist.
The bottom should slant down to a width of 45 to 60 inches.
The bottom should be 35 to 40 inches long.
Now sew together all the slanted edges of the fabric piece that you just cut. Make sure that you leave an opening of around 5 inches at the top. After that, hem the bottom. Sew a gathering stitch at the top, and gather the fabric in it until it matches your waist size. Your skirt is now ready.
Cut out a piece of fabric of following measurements in order to make bodice. The piece should be as wider as your bust, while the length should meet the measurement of your torso that is from collarbone to waist line. Now add darts to cinch the waist, it will also curve up the fabric at the bust.
Sew the bottom of the bodice up to the top of the skirt. Make sure that you line up an opening at the top of the skirt. Sew a zipper at the back of the skirt, and then hem the top of the bodice.