The thirteenth lunar tithi, Trayodasi, also known as Pradosha, has a special significance connected with Lord Shiva. It is on this day (Maha Shivaratri) that He swallowed Halahal – the poisonous fumes, to save the world. Hence every Trayodasi is called Pradosha and considered very auspicious. Divide the time from sunset to next sunrise into 5 parts and the 1st part, immediately after sunset, is called Pradosha time. Lord Shiva is at His happiest during the Pradosha time and fulfils all desires of those who worship him during this time and grants victory and success in all undertakings. There are two Trayodasis in a month and the Krishnapaksha Trayodasi is called Masa Shivaratri.
You can order a Pradosha Pooja. It will be done in your name and with your sankalpa, i.e., the specific purpose for which you are getting the pooja performed. This Pooja will be performed exclusively for you.