The best way to avoid streaks in a paint job is to paint carefully with high-quality paint, brushes and rollers. Thoroughly clean and prepare the surface before adding paint. If there is dust on your wall and you paint over it, the paint job will streak. Matching the paint may be difficult if you are not the one who painted the wall or ceiling in question. If this is the case, try and get as close as you can or prime over the paint job and select a totally different colour.
Look at the paint job. Determine if the paint itself is streaked or if there is something bleeding through the paint making it looked streaked.
Allow the paint to dry completely before trying to fix it.
Prepare the room for painting by covering furniture, taping off windows and covering the floor.
Look over the area that is streaked. If it is something in the paint job, like dust or debris, you may have to clean the wall and chip away some of the old paint very gently to get rid of whatever you painted over.
Use the exact same colour paint as the original paint job and paint over the streaks. You need to paint against the grain of the streaks this time.
Paint the area very evenly. Take extra care to make sure you are using the same amount of paint over the whole surface. Streaking is often caused by too much paint in some areas and too little in others.
Allow the paint to dry and examine your work. If you take care to paint evenly, the streaks should disappear.