Combine the tri-sodium phosphate, laundry soap, hypochlorite and warm water in a plastic bucket. Masonry Work Tools recommends this solution for cleaning brick surfaces. Scrub the solution on the brick, and rinse with fresh water. Pat-dry the brick before painting.
Remove any paint from the bricks with a wire brush and sandpaper. Rub the wire brush over the brick, and use the sandpaper for smaller areas. Wipe the brick off with a soft cloth, removing any dust or paint chips.
Apply a thin coat of masonry primer to the brick with a paint roller. The roller lets you make broad strokes over the brick and reaches more areas at once. Go over the brick a second time with the paintbrush, coating any areas you missed with the roller. Let the primer dry for several hours or overnight.
Paint the brick with a layer of masonry paint. While the paint is still wet, rub steel wool over the edges and the sides, which smears the paint and gives it a slightly distressed appearance. Let the paint dry completely, and follow up with a second layer of paint in a different color. Let the second layer dry overnight.
Give the brick wall an antique look by distressing each layer of paint. Once the paint dries, scrub the surface with the steel wool or sandpaper, which removes some of the new paint. Keep adding new paint and distressing the wall until you reach the look you want.