Self-sows freely; deadhead if you do not want volunteer seedlings next season. Water regularly, but do not over water. They handle dry heat quite well.
All of the methods that can be used to grow this plant:
By dividing the rootball
From seed; direct sow outdoors in fall
From seed; winter sow in vented containers, coldframe or unheated greenhouse
From seed; sow indoors before last frost
From seed; direct sow after last frost
Indian blanket, Brown eyed susan, Blanket flower