Fast on Mangal Vaar (Tuesday) is devoted to Mangal - the Planet Mars. It is believed that fasting for 12 Tuesdays helps overcome the malefic effects of this planet. All kinds of obstacles are overcome. It also brings fame and honor. Prayers must be offered to Hanumaan. Use of red clothes and red flowers is auspicious. Read Mangal Vaar Vrat Kathaa here.

Mangal Vrat is observed by those couples who wish to have a son. Other benefits include happiness in the family. People who believe in astrology observe fast to alleviate the harmful effects associated with the planet Mangal or Mars on this day.

Those who undertake the fast on Tuesdays take only a single meal. It is a whole day fast. The single meal on the day is usually any food made of wheat and jaggery. Food prepared of wheat and jaggery must be eaten only once in the day. After prayers to Hanumaan one must read the Kathaa.

Most people observe the fast for 21 Tuesdays without a break. People wear red colored clothes on the day and offer red flowers to Lord Hanuman. It is believed that Lord Hanuman will help his devotees in overcoming difficulties in life especially those that arises from the activities of Mangal Graha.

This Vrat is observed only for Hanumaan Jee also. The Vrat is for the whole day. In the evening, one should worship Hanumaan Jee, read Hanumaan Chaaleesaa, or Bajarang Baan, do Aaratee, offer Chanaa and sugar sweets (Besan Kee Bondee, or Besan Kee Barafee, or Boondee Ke Laddoo, Besan ke Laddoo etc) Naivedya to him. Apply Sindoor Tilak on one's forehead from his right arm. Distribute Prasaad and then eat food. Simple wheat dish with jaggery (or sugar) is all right. One may eat wheat Pooree with sugar mixed yogurt, or Meethaa (sweet) Cheelaa (sweet Dosaa of wheat flour).

Mangalaa Gauree Vrat
When this Vrat is kept on all Tuesdays falling in Shraavan Maas, it is called Mangalaa Gauree Vrat. This Vrat is mainly for Suhaagin women (women with husbands), but it may be kept by unmarried girls and women to get good husband, and men to get through their married life smoothly.

On this day After finishing one's daily chores, one should spread one white an one red cloth on a low stool (Chaukee). Establish nine Graha with rice on the white cloth and draw Shodashee Maataa on red cloth. Keep rice and flowers on one side of the stool and establish Ganesh Jee there; and establish a Kalash and wheat on the other side. Fill the Kalash with water. Make a four-sided Deepak (lamp) and put wicks of 16 threads. First of all worship Ganesh Jee, then offer Jal, Rolee, Maulee, sandalwood, Sindoor, betel nut, cloves, Bilva Patra, dry fruits and Dakshinaa. Then worship Kalash and after that worship Shodas Maataa and Nava Graha and give all offerings to Brahman.

Then make Mangalaa Gauree out of clay, bath her with water, milk or yogurt, clothe her and worship her with Role, Sandalwood paste,Sindoor Menhadee (Hina), and offer a flower garland of 16 types of flowers. Offer five types of dry fruits 16 in number, betel nut, clove, mirror, comb and bangles. Hear Mangalaa Gauree Vrat Kathaa (story) and touch the feet of an elderly lady, preferably mother-in-law. Keep fast and eat Anna only once. Next day eat only after flowing Gauree Moorti in a river.

After finishing all Tuesdays, one should do is Udyaapan (concluding part). One should not eat in Udyapan. One should sit for worship after applying Menhadee. Four Braahman should be invited for this Poojaa. Four banana stalks should be tied to the four legs of a Chaukee and put a cloth over those stalks. Establish a Kalash full of water, keep a bowl on it, and keep a Mangal Gauree in the bowl. Keep a Saaree and the things of Suhaag (eg Menhadee, Rolee, Sindoor etc). After the Havan, hear the Kathaa, do the Aaratee, feed the Braahman and give them one Dhotee and a thin towel (Angochhaa). Next day feed 16 Braahman with their wives, and give hem a Dhotee, Angochhaa and a box of Suhaag things. Then eat the food yourself.