The process of choosing paint colours successfully can be broken down into exact steps. However, your intuition alone can also guide you to the right paint colours...
Some people have no problem choosing paint colours, and can easily find just the perfect shade on their first try. But if you ask them how they do it, most will be unable to explain their process.
They will usually say: "I choose paint colours based on how they feel", or "I just know this shade will work here".
If you are not one of them, there is still hope! You too can develop your color intuition and taste by following the steps below. This process will train your "color sense", and make it easier for you to arrive at the perfect colour for your room, faster.
browse home decorating magazines to get clear on what colours and styles you like
inventory your existing home decorating color schemes to determine whether to re-use the existing colours, or introduce a new one
choose an inpiration piece to build your room color schemes around
determine the function of the room, so that your wall paint color is not only beautiful, but practical as well
decide what mood you are trying to create - that will help you narrow down your room color options
examine the lighting sources in the room, to make sure your room will lend itself to the colour
assess the sight lines in the space and take the color of the adjoining areas into account
test your chosen paint colour(s) to see how it actually "reads" on the walls
tweak the wall colour by experimenting with different values, intensities and undertones to coordinate with your furnishings, fabrics and accents
That's it! Follow this process for choosing paint colours several times, and before you know it, you will become a natural color expert (if only for your own family :)