Yes, soaked it in warm water. It bubbled and squeaked for a bit, when it stopped I pulled it out and it was very flexible and easy to form. In that state it doesn't hold the shape very well so you have to keep molding it as it dries. I'm very glad I cut the leather over sized so I could staple it down well outside of the stitch area. I've heard others say to make some relief cuts to get it to conform but I didn't have to with such a small knife. I put it in the oven for 10 minutes, took it out and did some shaping with a bone folder, then back in the oven for 10. Repeat.
Question: Would you have left the pocket clip on or removed it? I decided to leave it on, I think it gives the sheath interesting lines.