The simplest way to make a basement brighter is to repaint it. Choose a bright color to reflect the light entering the room. White is the best color for reflecting light. Paint all four walls and the ceiling the brightest white you can get from the paint store. Choose a water-proof white floor covering such as tile or just paint a concrete floor white in a basement for a utilitarian look.
Change your lighting from incandescent to fluorescent. Incandescent light bulbs cast a yellowish light compared to the white light shed by fluorescent lights. Fluorescent lights are also more energy efficient than incandescent light bulbs. Choose screw-in compact fluorescent lights to replace the incandescent bulbs in your light fixture in the basement. For even more brightness, replace a single bulb fixture with a fixture to support four fluorescent tube lights. These will cast more light than a single bulb, adding brightness to the basement. Place lamps in dark corners of the basement, or use floor lights pointed toward the ceiling to brighten walls and reflect off the white ceiling in the basement for more light without installing new fixtures.
Mirrors reflect images, but they also bounce light off their shiny surfaces. Arrange mirrors at the top of the walls near the corner with the ceiling angled at 45 degrees into the room. The mirrors will make the room look larger and reflect the light from the ceiling back down to the main area of the basement. Mirrors hung flat on walls directly opposite light sources will also brighten the room.
Just as furniture in a living room can make the space feel cluttered and dark, it does the same thing in a basement. If you are remodeling your basement into a living area or bedroom, opt for contemporary furniture in bright colors with simple lines, and put only the pieces you absolutely need in the basement. For example, if you are turning the basement into a man cave, do not clutter the space with a large dining table and sofa when a bar and chairs will suffice.