First step is to get a small ½, 1 or 2 gallon container with a handle to hold your paint. Fill the container enough to be able to dip your brush to at least to the halfway point. Your room should be ready to paint, all floors and furniture are protected and all prep work has been completed. Two important elements to using the brush is loading the paint and using the longest stroke possible. Learning to cut in straight lines is important and will take practice or tape.
When painting corners that will be the same color dip the brush halfway gently tap on the sides 3 or 4 times bring brush to the wall and spread paint gently at first, applying more and more pressure as your arm extends, go back and forth along ceiling or walls until all of the surface is covered and then feather off with one long stroke. Avoid flicking the brush so as to avoid splashing the paint. As you begin to paint in the areas that need less paint you should dip just the tip of the brush and in some cases wipe excess paint back into the container. Depending on how porous the substrate is will determine how quickly the paint will set up. After painting for about 5 minutes go back and look over your work. If you are seeing the paint starting to sag than you should spread the paint out further by applying more pressure to the brush and or cover more area with the paint you have on the brush. When brushing large areas where accuracy is not as important, such as corners and large trim such as wainscot paneling that you don’t want to roll, it is best to grip the handle of the brush with all your fingers. When cutting in an area that require more accuracy, it is best to grip the ferrule (this is the metal part between the heel of the bristles and the handle) with your fingers as this will give you more control.
When cutting in a ceiling, different color walls, cabinets and trim, your ability to create a straight line will be determined on how well you control your brush. The brush should become an extension of your arm and two methods will help in this process. First always try to position your body so that you are relatively comfortable. You should use your body and shoulders first to move your arm and only slight movements in the elbow and wrist. It is much easier to have a steady brush when the only movement is in your torso and or shoulder. Let’s say you’re cutting in around a door frame (a vertical line) starting at the highest point. Keep your wrist locked in a comfortable position, bend your elbow slightly 30-40 degrees and now by simply moving your shoulder up and down, leaning back and bending your knees your brush will move down the wall with a steady movement. For a horizontal line you will lean your body to the left or to the right remembering to keep your elbow and wrist as stiff as posible. By having the proper amount of paint on your brush you will be able to cut in the frame with one or two passes. Another benefit of this movement will be that your brush stroke will be much longer. If you brush by using your wrist you will find it will take much longer to do, be less accurate and you will most likely see your short strokes on the finished paint job. Remember always use the longest brush strokes possible and that goes for the roller too. Regardless of your cutting process you should always feather off with a large stroke. Once you have gained some confidence in using this method you will begin to see the importance of using mostly using your body and shoulder for moving the brush. Another important thing to do with your brush is to first spread the paint evenly about an inch away from the cut line and then go back with long strokes using the tip of your brush to push the paint into the corner. In tight areas such as around curved or angular trim the best method is to spread the bristles out by putting pressure on the brush, this way only a portion of the tip of the brush will be on the surface. Vibrating your wrist gently to push the paint into the crevices and around the objects you want to keep clean.
Remember to not let your brush dry out while using the roller of if you need to stop painting, simply stand your brush in the paint bucket or clean it.
When it’s time to clean your brush always use cold or warm water. Most brushes have a firmness to the bristles which would be destroyed if you were to use hot water. Hence a very floppy brush that will not release the paint well. There are also 3 more things to do before storing your brush. Use a soft wire brush to remove dried paint from the ferule and heel of the brush, next take a steel comb and insert into the heel of both sides of the brush several times, being carefull to brace the brush to avoid the points on the comb. This will open the bristles and allow you to thoroughly remove all the paint from the brush. When there is no more paint residue coming out of your brush then you know it is clean. The comb will also keep the bristles straight. Last but not least store your brush in a brush holder which usually with the brush when you purchase it. Recently I have seen plastic brush holders on the market and they do work very well in keeping the bristles straight. It is very important to keep your brush in its original shape.