An extraction order can be created in the window of the corresponding deposit or extraction building. Choose the tab "Orders , then click "Create" or “Create an order” in the building window, then specify the duration of work and salary you’re going to pay for it. Any work order immediately appears on the announcement board at your plot and on the general labor market. To check it out, click "All jobs".
For example Iron ore quarry extraction order
Another way is to go to the "Orders" tab and click "Create".