Most store bought juice is pasteurized, so no need to worry about sterilizing it. (Those that aren't pasteurized will have preservatives that will prevent your pitched yeast from taking off, so avoid those at all cost). You may be able to get an orchard to press you a special batch without adding preservatives, in which case you can just leave it be and let the wild yeasts do the work. If you want a more consistent fermentation, or just the peace of mind of using your own yeast, you'll want to use a campden tablet (potassium metabisulfite) 24 hours before pitching to sterilize it.