Clean thoroughly (since it's been 12 years)..........might even want to reapply some primer such as Loxon Masonry Primer from Sherwin-Williams. Normally you wouldn't have to do this, but, with a 12 year lapse in coverage, it might be a prudent idea. After primer dries apply one or two coats of your favorite paint. My recomendation is SW's SuperPaint Satin latex. Avoid flat for exteriors as they are "dirt collectors" in my opinion.