Summarize the following:
Multiply the total width of the accent wall by the height of your ceiling. This tells you the square footage of the accent wall. Typically, 1 gallon (3.8 L) of paint covers around 350 to 400 square feet. Divide your total square footage by 350 or 400 to figure out how many gallons of paint you’ll need to cover the wall. A single gallon is enough for most walls, but keep in mind you’ll probably need to do 2 coats.  If there are windows on the accent wall, subtract 15 square feet from your total square footage. Then divide that number by 350 or 400. If there's a door, subtract 21 square feet before dividing by 350 or 400. Take off the outlet covers, fixtures, switch plates, and window coverings before you get started. Use painter’s tape to mask off the window sills, door hinges, baseboards, etc. Protect the floor with a tarp and cover any furniture in the room. Crack a window or get a fan so that the room stays ventilated. Since the color of the accent wall will contrast quite a bit with the ceiling and other adjoining walls, it’s important to get a straight, clean line where the accent wall meets them. Crooked or smudged lines will be very noticeable. Apply the tape slowly and be precise for best results. Dirt and debris will prevent the paint from adhering well to the wall, so always clean interior walls before you paint them. Create a mild cleaning solution with warm water and a few drops of dish detergent. Wipe the wall down with a sponge or cloth, working from floor to ceiling and in small sections. Let the wall dry completely before moving on. Primer isn’t required, but it’s recommended. It will help the paint adhere to the wall, allow for better coverage, and help the paint wear better over time. Buy an indoor paint primer and apply one coat to the accent wall with a roller or paintbrush. Let it dry completely before you start painting. Use a latex-based interior paint for this job. Start applying paint in one of the top corners, working from the ceiling to the floor in small sections. Use an angled brush to get into the corners, then switch to a roller to cover the main wall space faster. Use the angled brush anywhere you need to do detail work.  Wait for the first coat to dry, then apply a second coat the exact same way. Let the last coat of paint dry completely before removing the painter’s tape and replacing fixtures.

Summary:
Calculate how much paint you’ll need. Remove the fixtures on the wall and put down protective tarp. Use painter's tape to create clean lines on the adjoining walls. Clean the wall before you paint. Brush on a coat of primer for the best paint coverage (if desired). Apply 2 coats of your chosen paint for the best finish.