I wear my Kholsters for atleast two weeks as much as I can before "combat" cutting them. That way the leather breaks in a little, making it a little easier to cut and the leather also starts to mold around the gun and my body by that point, helping me know where to cut it. I like to cut from one side and cut under the little notch that the magazine release will leave in the leather, because if I don't, sometimes the mag release gets pushed during every day wear (not good!). I then go up, making sure there's leather between the slide and my body, finish cutting to the other side and then smooth out my cuts with a dremel sanding tool, so the leather isn't cutting into my skin. There are tons of videos on youtube about it, if you're a visual learner like me. I hope this helps!