[Jeff Higgins]

Absolutely never, ever, under any circumstances, apply any sort of oil, conditioner, cream, gel, or liquid of any kind to a leather holster. Doing so will ruin it. Leather softens over time. Holster makers know this and account for this - that's why they make them "tight" to begin with. Speeding the process in an unnatural way with any kind of liquid will only result in a prematurely loose, floppy holster.

On top of that, whatever you apply to your holster gets applied to your gun as well. Many leather conditioning products have ingredients in them that are harmful to the finishes on our firearms. Yes, even if you have a stainless steel firearm, some of these products can "stain" the firearm.

The best way to break in a new holster is to simply wear it all the time. Keep the gun in it all the time even when you are not wearing it. Yes, wrapping the gun in something like a plastic bag, or some prefer wax paper (I'm leery of what might be in the "wax", though), adds a bit more "stretch" and speeds the process. But nothing beats just wearing it all the time, and keeping the gun in it all the time. Even overnight, in the nightstand.