Friday evening: Shop for paint and supplies. If you are following the lead of Benjamin Noriega-Ortiz (the designer of the room pictured above) go for a clean cool white and a hot intense accent color - if the pink isn't your cup of tea, perhaps a dark charcoal, a deep navy or a lemony yellow?
Saturday: Move furniture, clean and prep the area. Paint the walls white. Stop, pat yourself on the back and let dry fully overnight.
Sunday: Take your time and measure up from the floor approx. 3 feet (give or take a bit, depending on the height of your bed/pillows), at regular intervals of approximately a foot along the entire length of the wall, marking the three foot spot with a pencil . Run good quality masking tape CAREFULLY along the marks, with the top of the tape hitting the marks. Paint the upper portion of the wall with your gorgeous color- don't overload your roller, especially near the tape. Resist the temptation to fuss with the tape too early - let it dry well before attempting to remove it. Remove tape. Clean up. Return furniture, admire your fabulous job and sleep well in your newly spiffy bedroom!