Before you go out to purchase curtains with valance, you will need to take some accurate measurements of the windows to be covered. Be sure to measure the width of the window as well as the height; when measuring the height, decide if you want the curtains to cover just the window area, or if you want the curtains to fall all the way to the floor. This is largely a matter of preference, but as a general rule, if the room has electric heaters that run along the base of the walls, full length curtains with valance may not be the best choice.
The curtains with valance should usually match, but sometimes it may be acceptable to have a curtain and a valance of different colors or patterns. Regardless of the colors, the curtains with valance should complement each other and not clash too harshly. Many homeowners like to match the color of the curtains and valance with the carpets, walls, or even the furniture, which is a great way to ensure a consistent decor within the room. The existing colors in the room can also be complemented with a different color of curtain with valance, though it is important to choose a color that will not clash with the existing colors.
The size of the curtains with valance will depend on the measurements you took of your windows. They should generally be wider than the window itself, and depending on the style of curtains with valance, the fabric may be quite a bit wider than the windows because they are designed to avoid lying flat. The curtains may be ruffled or otherwise folded to create a more three dimensional look, thereby adding to the overall aesthetic of the windows and the room.
Think about the available light in the room when choosing the color and thickness of the curtains. Thin curtains made of silk or other fine materials are a good choice for rooms with little available natural light. The windows can be blocked by such material without blocking all available sunlight, thereby allowing the room to appear brighter even with the curtains closed. Thicker curtains will block out most, if not all, available natural light, so choose these types of curtains if you want to create a dark room during the daytime. you may also consider thicker curtains if your windows are single-paned; the curtains can help insulate the room during cold weather.