First of all, you must choose quality color for durable and beautiful painting.  Just follow these steps below which you can do it yourself.
Step 1: Preparing the surface
This step is the most important to clean and prepare the surface correctly for perfect painting.  Before your first pain, you have to make sure that there is no any dust on the surface.  You may clean it with plain water or soap water and then clean it again.  If some mildew or moss grows, eliminate it with cleaner.  If the wall is old and former paint is shabby, you need to peel it out.  You also repair peeling before with latex primer and latex paint.
Step 2: Foundation Painting
Paint color for foundation is used to paint first that helps the top coat adhere to the paint below as well as protect damage from chemical reaction between exterior paint and the surface.
Concrete Surface: If it is new, you should adjust the surface and other pieces with new foundation.  But if it is previous surface, repaint with the same color for smooth and quality painting.
Wooden Surface: Paint with foundation for wood to keep resin from effusing to the top coat and prepare the surface smooth for beautiful painting.
Iron Surface: The foundation helps prevent rust and support adherence of the top coat.
Step 3: Top Coat Painting
There are piles of exterior colors for your choice.  You should leave the first layer of paint dry before painting next time (2-3 times of painting top coat).