Here's my quick guide to making a corset. I used Butterick 4254 and I was making 18th century stays. The pattern itself explains things well, this is actually more a quick tips guide.
#2: Don't use interfacing, just use two layers of heavy home decor/upholstery fabric, twill or duck.
#4: Then I use these Heavy-Duty Cable Ties to bone the corset. Much less expensive and easier to work with than steel. Or so I've been told. I've never actually used steel.
#5: I cut them to length with a razor blade and label them with a sharpie.