Peasants are known for their workmanlike and a bland sense of style, but that doesn't mean dressing up as a peasant has to be boring. Remember that peasants were typically a poor class, and your costume design should reflect that. Most of the clothing peasants wore were considered to be basic pieces, so avoid wearing anything too fancy, such as jewelry and posh fabric.
Peasant Costume for Men
Wear a pair muslin tunic as your top and layer a vest on top of that. The vest can either be lace up or button up in the front and can be sleeveless or not.
Put on a pair of cloth stockings then a pair of cross-gartered breeches. Tattered clothes with holes and a little dirt can help add authenticity to the peasant clothing.
Wear a pair of low-cut wood or leather shoes similar to moccasins. Tousle your hair to give it a messy appearance, and finish your look by putting on a wide, flat brimmed hat. If the weather is cold, you can add a cape.
Peasant Costume for Women
Put on a long-sleeved muslin shirt and at least one long skirt. Peasants often wore two skirts, with the nicest skirt layered on top of the underskirt. Tuck the shirt into your skirt and put on a vest or tight fitting bodice.
Tie a long apron around your waste and put on a pair of cloth stockings. Tie hair up under a biggens or coif. Lastly, slip on a pair of leather shoes or go barefoot, if possible.
Hold on to a simple woven basket if you wish to accessorize. You can also wear a cape for warmth.
When picking out fabrics, stick with natural fibers such as cotton, muslin, leather, wool and twill.
Avoid denim, polyester, silk, satin, and other man made or lavish material.
Stick with earth tones and basic colors such as rust, brown, yellow, green, orange, blue and red. Avoid fabrics with prints.