Reborn Fanatics Odourless Silicone Solvent gives more working time than Novocs and are relatively cheaper but just as effective.
Before painting silicone, a thin coat of Odourless Solvent will open up the silicone's pores aiding a better paint bond. The Solvent will evaporates into the air as well as soaking into the silicone and helps draw silicone paint into the pores.