This group is the most difficult to categorize. Women who fall into this category choose their clothes for their simplicity, classic style and ease of wear. While they still seek to express their religious convictions through what they wear, they also are much more likely to choose to blend in with the dominant fashion styles. Skirts and jumpers are popular, and trousers for women tend to be perfectly acceptable. Least likely of my religiously observant dress designations to choose to cover, women in this group are most likely to have shorter hair styles, as shorter can be simple and easy to care for. Makeup is often avoided as a statement on simplicity, but jewelry is common, particularly earrings. Actual plainness (solid colors, simple print, limited-palette wardrobes) is a hallmark of the plain-modern look. There are neither anachronisms nor symbolically and there are no traditionally important items.
Some plain modern resources:
DEAR Friends, In the Power and Light is my Love to you all, in which the Vertue, Life, Holiness and Righteousness is known, and the Riches, that never fade away. Live in the Truth, which ye first received, that it may be your Crown, and your Cloathing. And dwell in Love, and Peace and Unity one with another in the Truth of God, . . . and keep your Meetings in the Name of Christ Jesus . . . in whom the Peace, Life and the Blessing is. . . . And all know one another in him, who is the Substance, and him to be ...
I am not Amish or Mennonite, but some people who come to my website are interested in knowing more about these groups. I can recommend these books as authoritative and relatively inexpensive sources of further information.