Simple squarish neck, moderate width sleeves. The neck is fairly wide and does not show under the other clothing. The sleeves are usually rolled up to the elbow for work. You may want to leave the sleeve open at the bottom in order to be able to roll it up.
Underarm gussets are necessary to have sufficient freedom of movement.
This is a square-necked, sleeveless underdress that is probably pretty shapeless. It goes over the chemise and under the bodice. It may not be full-length. Wool, sometimes linen. Earth colors, reds, russet, yellow, brown, dark green, dark blue, grey, charcoal, are all good colors.