Even though Mélilot has a loose, casual feel, it curves in at the waist and has a slim fit at the hips. If your measurements correspond to different sizes, the solution to get a nicely fitting shirt is to grade between sizes.
In this example, we will be grading from 40 (bust) through a 38 (waist) up to a 42 (hips).
Start with the front bodice (#1). Trace the top of the pattern piece in a size 40, including the dart and position marking for the pocket. To grade between the bust and the waist, use a French curve to draw a curve between the lines for sizes 40 and 38, from the bottom of the dart to the waist notch.
To grade between the waist and hips, use the French curve to draw a curve between sizes 38 and 42 starting at the waist notch and ending at a point 1 1/4 inches above the bottom left corner. It is very important to keep that last segment vertical, to prevent the sides of the shirt from sticking out.
Trace the bottom of the bodice in size 42, along with the straight grain arrow and markings for buttons and buttonholes. Cut out your pattern piece.
Now trace the top of the back bodice (#2) in a size 40. Use a French curve to draw a curve from the bottom of the armhole (in size 40) to the waist notch (in size 38).
Flip your front bodice pattern piece and place it above the back bodice piece, so that you can trace the curve that goes from the waist notch to the hips. Trace the bottom of the back bodice in size 42.
Trace the rest of your pattern pieces (sleeve, cuff, collar and collar stand, etc.) in the bust size (here, size 40).
This should let you keep this flattering curve that gives Mélilot a little extra something 🙂
