Amish women wear prayer caps, in accordance with a scripture in Leviticus. Men usually grow beards. Women can not wear pants. Both sexes are forbidden from wearing buttons that are visible (because these are considered ostentatious). Some Amish societies do not allow pockets because of the nice things that one could put in them. They don't want anyone to flaunt their wealth. Christmas is not commercialized, and the focus remains on religion. Gifts are few in number. Children return to school the following day.
Education rarely exceeds middle school or high school level. Amish societies are mostly agricultural, and every community member is kept busy with running the farms. Amish education allows for agricultural life, meaning that students are let out of school for important parts of the agricultural season.
Amish religion is strictly biblical, and family is highly valued. Community members take care of each other in the event of a crisis, natural disaster, etc. Amish people pay in cash, and save until they can afford what they need. Credit is frowned upon. Amish societies are usually insulated from the outside world to some extent. They attempt to be self-sufficient and their economy is usually the last to be affected by an economic downturn.
Amish people avoid modern technology whenever possible. When an Amish child reaches a certain age they are allowed to experience modern life. They use electronics, and venture out into the modern world. They experiment. Then, they must chose whether to remain in an Amish society or to join modern society. If they join modern society, they must not return to their Amish community.
I'll try to elaborate on this in a few hours. Then I can quote you the scriptures that dictate Amish dress.