Shades let in the most light when they are raised, but in this position they provide the least amount of privacy. Shades make the floor space in front of a bay window appear larger because the shades end at the base of the window instead of extending to the floor like drapes. If you have an especially large bay window you want to use for a separate seating area and want to maximize your space, shades are a good option. Look at each panel of the bay window as a separate window, covering each part with shades accordingly.
Blinds are similar to shades in the clean, sleek look a bay window has covered with them, but blinds provide both light and privacy at the same time, where shades do not. Miniblinds over each section of a bay window gives the old-fashioned window a contemporary look. White blinds over a large bay window will make the space appear even larger. Opt for dark blinds to minimize the expanse of the bay window.
Cafe curtains are a good option for providing privacy for a seated dining area in the alcove made by a large bay window. The curtains cover the bottom half of the windows, while light comes in from the top of the windows. These are usually are accompanied by a valance at the top for decoration. Cafe curtains give a bay window an informal, old-fashioned look, especially if the curtains are finished with frills or made of lace. Cover each section of the bay window with its own cafe curtains and valance to open the space in front of the bay window to use as seating.
Drapes over the entire bay area can make a bay window look like a flat window when the drapes are closed. Floor-length drapes will completely cover the bay area made by the window, creating a reading nook or study area that is private from the inside of the house but takes advantage of all the light admitted through the bay windows. Placing the drapes across each of the bay window sections blocks makes the bay window look larger, especially if you use light-colored or sheer drapes.