Dhanteras is the first day of Deepavali. Dhan refers to wealth; hence, this day is celebrated to worship Lakshmi, the Goddess of Wealth. It is also called Dhanvantari Triodasi . It is in fact the thirteenth lunar day of Krishna Paksh, the dark forthnight of the month of Kartik. According to the Ayurveda it is the birthday of the deity Dhanvantari, so on this day Ayurvedic doctors (vaidyas) worship Him. On this day, Lord Dhanwantari came out of the ocean with Ayurveda for mankind. This day marks the beginning of Deepavali celebrations. At sunset, Hindus bathe and offer a lighted diya with prasad (sweets offered at worship time) to Yamraj, the Lord of Death and pray for protection from untimely death. This offering should be made near a Tulsi tree, or any other sacred tree .
Another name for the first day of Deepavali is Yamadeepdan. This name is associated with Yama, the God of Death. The sixteen year old son of King Hima was destined to die on this day. However, the devotion of his wife impressed Yama so much that he returned without taking the Prince's life.
On this day, earthen lamps are lit for ancestors of the family and the lamps are floated down a river or pond. Lamps are also lit at the entrance of homes. Offerings comprising of water, rice, jaggery, vermillion, and flowers are kept for Yama. In South India, this day is known as Asweyuja Bahula Thrayodasi. It is a very auspicious day and every household celebrates by buying silver, gold and utensils. In their homes, people literally wash coins in milk and water and worship Lakshmi, the Goddess of Wealth. They also distribute money to the poor and needy.

2. Choti Deepavali

The second day marks the celebration of Choti Deepavali. The second day of Deepavali is called Narak Chaturdasi. On this day Lord Krishna destroyed the demon Narakasur and made the world free from fear. On this day, one should massage the body with oil to relieve it of tiredness, bathe and rest so that Deepavali can be celebarated with vigour and devotion.
This day is also known as Roop Chaturdasi. Hindus perform a ritual bath and meditate in order to enhance their beauty. In connection with this, the second day is also referred to as Kali Choudas. People apply kajal (black eye liner) to the eyes in order to ward off kali nazar (evil eye). It is said that on the night of Choti Deepavali, you should not light the Yama Diya.
In Andhra Pradesh, this day is known as Divvela Panduga. At the end of this day, people take a bath with oil, accompanied by the bursting of firecrackers.

3. Lakshmi Puja

This is the actual day of Deepavali, commonly known as the Hindu New Year. Third day is basically dedicated to the worship of Goddess Lakshmi, consort of Lord Vishnu, to receive blessings of wealth, prosperity, triumph of good over evil, light over darkness. For Jains, this day is known as Deva Deepavali. On this day, homes are brightly lit, and scriptures are read in order to worship Lord Mahavir. Kashmiri Pandits celebrate this day as Sukhsuptika, which literally means sleep with happiness. Badhausar is the name given to this day in Gujarat. It is believed that on this day, Goddess Lakshmi visits all homes that are brightly lit.
In some south Indian states, Deepavali is known as Balindra Puja. On this day, a puja is performed to Lord Krishna and an offering of oil is made. Sikhs celebrate Deepavali as Bandi Chhor Divas. This day is celebrated as a day of freedom by the Sikhs. Sindhis celebrate Deepavali as Diyari. They too perform a Lakshmi puja on this day.

4. Padwa and Govardhan Puja

The fourth day of Deepavali is usually celebrated as the New Year for most Hindus and is called as Bestavarsh. It is believed that Lord Krishna gave his protection to a cowherd family in Vrindavan to save them from the anger of Lord Indra. Hence this day is also termed as Annakoot. In Karnataka, this day is celebrated as Bali Pratipada. On this day, the demon king Bali descends to the earth to visit his loyal subjects. Bali Maharaja was defeated on this day by Lord Krishna's dwarf incarnation, Vamanadeva. This day also ritually celebrates the love and mutual devotion between the wife and husband. Generally no money transaction takes place on this day.

5. Bhai Duj

The fifth day of the Deepavali is called Bhai teeka. The fifth day is also referred to as Yamadwitheya. It is a day dedicated to sisters. In the Vedic era, Yama (Yamraj, the Lord of death) visited his sister Yamuna on this day. He gave his sister a vardhan (a boon) that whosoever visits her on this day shall be liberated from all sins. They will achieve moksha or final emancipation. From then on, brothers visit their sisters on this day to enquire of their welfare. On this day, the sister applies vermillion on the forehead of her brother and prays for his long life
This day marks the end of the five days of Deepavali celebrations. This is also known as Bhai fota among Bengalis. Bhai fota is an event especially among Bengalis when the sister prays for her brother's safety, success and well being.
This day marks the end of the five days of Deepavali celebrations.