I consulted Jerry Thomas for guidance:
I took two large, very ripe peaches, and smushed them up good, skins and all , with the bottom of a rocks glass. I spooned them into a mason jar, and then filled the jar with brandy to the top. I mixed it around a little bit to ensure a happy marriage of brandy and peach. Thomas recommends letting the mixture macerate for 24 hours, which means in the future this mixture could be made on relatively short notice. However, I'm going to Alaska tomorrow morning for two weeks. How could letting it sit a little longer possibly hurt? It could only improve the flavor, right??
So I've just covered the jar, and pushed it to the back of the fridge. See you in two weeks, Peach Brandy! When I return, I will strain the liquid, and mix some cocktails.