No need to pasteurize after bottling. You want to sanitize all of your equipment, of course, and be sanitary when you bottle. You can use campden tablets (potassium metabisulfite) when you bottle if you'll be aging the wine for a while if you want. Sulfites work as a preservative and antioxidant, but aren't strictly necessary. I use sulfites, but many others do not.
Broken Leg Brewery
Giving beer a leg to stand on since 2006