Arslan. wrote:
.... For those that are non-emphasized sunnas, one follows the tashahhud in the first sitting with sending blessings upon the Prophet
before standing for the third rak`a, which one then begins with the opening supplication (thana`) and seeking refuge (ta`awwudh) before the basmala and Fatiha.
Source: Maraqi 'l-Sa`aadat, Page 98, footnote #339