Even if you think you'll probably do the job yourself, it's good preparation to seek estimates from professional exterior home painters near you. Then you'll have a financial point of comparison and you may benefit from what a home painting contractor has to say about the condition of your home, color choices and types of paint available. Let the painter make his pitch for a professional job before you decide what to do. You can still opt to do it yourself while having learned something worthwhile.
Picking exterior house paint colors is a lot different than picking a color for a shirt or a car. It may help to drive around to observe colors that other homeowners have combined on homes that are of similar size and design as yours. There are also online resources that provide homeowners with the ability to create virtual makeovers of their home by combining colors together through their software programs as well.