I'd hand-stitch the pleats and machine stitch more-or-less everything else. Well....

Let's do it this way.

1. if you have to blind-stitch and hem the fabric, best to do that by hand.
2. the right-hand edge (the fringed edge) of the over apron can be "stitched in the ditch" and you won't see the stitching as lot as you plan the fold-over carefully. Then you do a few hand stitches at the hem and at the waistband and press the bedickens out of it with an iron and a damp towel and you're good to go.

3. the little tucks and bobs and so on to refine the fit are best done by hand.

4. the interfacing or better...hair canvas that you put in the front can be attached by machine.

5. The reinforcing strip in the back , across the cutout pleats will have to be hand done.

6. the steeking will have to be hand-done

7. attaching the waistband can be done by machine, though.

8. The fold-over and final attachment of the waistband will be hand-done.

9. making the buckle straps can be done by machine, and attaching them can be done by machine. I STRONGLY , STRONGLY encourage you to look into how Matt attaches the buckle for his under-aprons. It's MUCH easier than the traditional method. I make all my tartan kilts that way, now. That has to be hand-done.

Upshot is, you can do some of the kilt by machine and nobody will know. When I make a tartan box pleat, I sew the tapers to each other by machine. I still have to rip one out, but it's so much faster than hand-sewing that it's worth it. I can make a nice, wool, 4 yard box pleat in about 15-18 hours, now.