The lighting is also important. Not surprisingly, bright lights keep us awake. So too, does light with a "cold" or bluish tinge - such as from fluorescent lights. This is, after all, the lighting of the early morning sun. On the other hand, the twilight sun is full of warm shades of orange and red. So the light from a dim bulb or, better still, from a candle, oil lamp, or natural fire, will be much more relaxing. Combine these with pink furnishings, soft slow music, the sound of waves on the beach ....
Be sure to consider lighting when you design a bedroom. Bright, blue or cold lights tend to wake us up. An example of these are the fluorescents. That's because they imitate the early morning sun. At twilight the sky has the warm colors of orange and red. The most relaxing lights for nighttime come from low wattage bulbs, candles, oil lamps or a nice fire. If you add these lights to pink furniture, soft and slow music, the waves on the beach you get the picture.
How do we get around not putting a candle, oil light or open fire in a child's bedroom? One way is to use electric bulbs that flicker. There are also fiber optic lamps available that create a low level light, changing from one color to another. The slow, gentle changes are relaxing, assuming that they aren't too bright. Some children like to sleep in a completely dark room. This is when the thick curtains will come in handy to screen out late night and early morning summer sun.
Since it's pretty unlikely that a parent would wish to put candles or oil lamps in a child's room, there are other options to consider. You can find fiber optic lamps that are very relaxing, even if they don't flicker as low as 7 Hz. They do, however, change color slowly and the level of light is very low. The changing colors and soft light are so calming that they should be very helpful in getting your child off to sleep. Also available are lights that flicker so as to resemble a small flame. There are some children who prefer to sleep in a totally darkened room. If this is the case in your family, consider the heavy curtains that block twilight and early morning sun.
Humidity and fresh air. In the winters we tend to have the windows closed, and the heating on. The closed window cuts out the outside noises, but also cuts out the fresh air. Furthermore, the heating dries out the air, which in turn dries out our nasal passages. Stuffy air and uncomfortable noses are a common cause of poor sleep and wakening in the late parts of the night. Opening the window a crack may help.