The best first step is to seal any type of openings that are encouraging the stink bugs to get in. They also are drawn to moisture, so ensure these areas are dry.
Bay leaves have a strong, almost-medicinal odor. The scent doesn't hurt stink bugs, but they don't like smelling it and are less likely to approach an area that smells of it.
You can purchase a bay leaf plant to grow in your kitchen or just the dry bay leaves, often found in the spice aisle, to place around windows and doorways.