In my story "The Mountaintop," set in ancient Greece, there were so many things to research, but as far as clothing goes, the Greeks made it an easy time.
The Ancient Greeks were not fussy about their clothing. Ancient Greek clothing was typically homemade, and the same piece of homespun fabric could be used as a type of garment or blanket. The garments were made for function, and they were made simply. For every member of the family, except for infants who often wore nothing at all, an outfit usually consisted of a square or rectangular piece of fabric, pins for fastening, and sometimes shoes and/or hats. The style and type of the garment depended on who wore it, and the job or function required of the person. There were several types of garments, all derived from a basic tunic. The tunic was worn by both men and women, varying in length according to gender. And with Greek summers being brutally hot, the less fabric and complicating seams to deal with, the better.
From Greek vase paintings and sculptures, we can tell that the fabrics were intensely colored and usually decorated with intricate designs. The colors used during this period were brightly-hued, such as green, indigo, yellow, violet, dark red, dark purple. The white ideal comes from paint that had once covered the marble statues wearing off by the time they were found.
Clothing for women and men consisted of two main garments--a tunic (either a peplos or chiton) and a cloak (himation).
The peplos was a large rectangle of heavy fabric, usually wool, folded over along the upper edge so that the over fold would reach to the waist. It was placed around the body and fastened at the shoulders with a pin or brooch. There were armholes were on each side, and the open side of the garment was either left that way, or pinned or sewn to form a seam.
The chiton was made of a much lighter material, normally linen. It was a very long, very wide rectangle of fabric sewn up at the sides, pinned or sewn at the shoulders, and usually girded around the waist. Often the chiton was wide enough to allow for sleeves that were fastened along the upper arms with pins or buttons. Both the peplos and chiton were floor-length garments, usually long enough to be pulled over the belt, creating a pouch known as a kolpos.
Under either garment, a woman might have worn a soft band known as a strophion, around the mid-section of the body. Men in ancient Greece customarily wore a chiton similar to the one worn by women, but knee-length or shorter. An exomis (a short chiton fastened on the left shoulder) was worn for exercise, horse riding, or hard labor.
The himation worn by both women and men was essentially a rectangular piece of heavy fabric, either woolen or linen. It was draped diagonally over one shoulder or symmetrically over both shoulders, like a stole.
A few other pieces still based on the general shape were also used at times. Women sometimes wore an epiblema (shawl) over the peplos or chiton. Young men often wore a chlamys (short cloak) for riding. Greek babies wore cloth diapers when it was hot and when it cold, they were wrapped up in blankets. Most of the time children wore only cloth (resembling shorts) wrapped around their middles.
A simple dress for a not so simple culture.