On this (Amavasya) day Hindus devotees, especially perform “Sharadh” and “Tarpan” for dead ancestors.
Shani Amavasya is a very auspicious day (lucky & blessed) for Hindu devotees. On this day people visit temples or Lord Shani temple and offer him mustard oil, flowers,it very strongly believed by doing Shani puja, you will get his immense grace or blessings from Shani Dev. Troubles will get desappear and free from evils.
Shani Sade Sati
Peoples who have affect of Sade sati or Shani Dosha present in kundli (lagan chart/birth chart), suggested strongly to worship lord Shani with complete methods of pujas. It reduces the bad influences or bad results during the saturn planet periods. If unable to pray lord Shani with method during Shani amavasya, at least you can Donate / offer mustard oil to Shani Dev on this day.
Saturday is a day in week to dedicated to worship of Shani Dev. Worship of Shani Dev bringing fortune and prosperity in your life.