I used Past Patterns no. 106: 1901-1908 "Straight Fronted" Corset, with a combination of rigid steel boning (on the front, back, and over the hips), and spiral steel boning on the rest of the seams to allow a bit of movement. I added extra boning along the edge of the split-busk at the front, to help with that infamous 'pigeon breast' silhouette (which is hard to get across on a modern mannequin, but it works on a human!). The boning cases are embroidered with white thread, in a method known as flossing, which holds the boning in place and keeps the tension.
It's made in white coutil, with grosgrain ribbon edging, and elastic suspenders.
I added some antique lace I found in the sewing room at Polesden, and an ivory bow at the front, which was common on the wedding corsets of the time and again adds to the silhouette once you've put a corset cover on top.