What is the last thing on your mind when you are closing your eyes at night ?
paint the walls white. you want your room to be as light as possible because there are no windows. decorate with light colors as well, like, wellwhite! but of course, add colorful accents so it isnt too white. like maybe some pink throw pillows?
try and use themes and colours that lighten the room as it is a basement. Put up a large print of an outdoor scene like a window framing the garden or similar. Use light colours and a touch of yellow to look like sunlight. Some pinks and yellows look good together so maybe a quilt cover with a modern theme in these colours. Maybe white furniture.
A chevron is a symbol seen a lot on military uniforms. One for private, two for corporal, and three for sargent.
