Tejadi , a sindhi festival celebrated during the rainy season in the scared Hindu month of Savan or Shrawan [Shiravan]. In fact this is a kind of fast observed by ladies for the life and well being of their husbands.
The Sindhi fragrance of this festival lies with "Asur" [early dawn food taking] and Mahendi. Hindu Festival "Karva Choith" [young generations born abroad might have seen this festival in Indian movies] of north India and this sindhi festival resembles to a large extend for way of celebration and purpose, the only major difference is Teejadai is celebrated in the Shrawan month where as Karva choith is celebrated on the forth day after the full moon day in the month of Kartik.

Schedules of Tejari day :
In the hours of early dawn food (Asur) is taken and after that work of creating artistic Mehandi get started. Teejari fast starts from the sunrise and ends with moon rise.

After keeping fast for whole day, at night "Argu" [Milk, rice & sugar] is offered to moon, but before that ladies recites "Katha of Tijadi Mata" and food is taken afterwards. To mark the festival mood at some cities Mahendi competitions are also arranged on this day.
In the evening all the ladies dressed up with jewelry and other sings of being wedded and go to near by temple for listing Katha. After the moon rise they see the moon and soon after that face of their husband this marks the end of fast and celebration.

Historical Backdrop
According to Puranas there was a married woman named Karva, she was said to be have Shakti  just because of her immense love and dedication towards her husband. Once while bathing in river husband of Karva was caught by a crocodile and was like to die but Karva with her spiritual powers not only saved life of her husband but also tied the crocodile with cotton yarn and asked Yama for sending the crocodile to hell. First Yama refused to do so but remembering the powers of Karva and under the influence of fear of being cursed by her agreed and sent the crocodile to hell.
In the Mahabharata era Dropadi also observed this fast.

According to another version Queen Veervati was lost not only her status of queen but her husband also fall ill just because of completing the fast before the actual moon rise. (Veervati was sister of seven brothers and was fasting for Karva choith at her mother's house after marriage, due to fast she was fainted towards the death end of evening, seeing this brothers have generated a fire behind mountains and asked her, to end the fast because that was moonlight). On the advise of Goddess Parvati, Queen Veervati served the ill husband and finally was able to get back love and affection of her husband.