If you're a typical DIYer, you've probably decided, at some point in your life, that some room in your house could do with a new paint job. If you decide to leave the paint color the same, all you have to worry about are things like taping and moldings and windowpanes. You know, the easy stuff. But what if you want to change the color? Then what? Now you're getting into the murky realm of Interior Decorating, where people get degrees to tell them when, if ever, it's okay to put blue and purple in the same room. (True blue and royal purple, for example, should never go in the same room. But powder blue or baby blue look very nice with a soft lavendar...)

First off, it's important to know the basics. There are four basic color groups that you'll want to worry about when painting; neutrals, brights, pastels, and earth tones. (Arguably, there are other color groups as well, such as Neons or Metallics. But we're hoping you won't be using those to paint your walls...)

Neutrals are colors like tan, camel, brown, coffee, bone, ivory, etc.; colors that go with almost everything and that can be used as a backdrop when you don't want something to stand out. Neutrals are good choices for rooms that have a lot of interest in the decor or the furnishings. Museums, for example, generally choose neutrals for their walls; the point is to showcase the paintings, not the walls. Similarly, rooms that have collections in them, or rooms where the furnishings or some other aspect of the room is meant to be the focal point, neutrals are a good, safe color. If you're not entirely sure what you're doing, pick a nice neutral and run with it. It's very hard to come out wrong with a neutral.

Brights are the opposite. Where neutrals practically create their own background and fade into it, brights stand up and scream "Look at me!". Brights are used VERY rarely as a wall color, no matter what you might see on Trading Spaces, and when you do use them, you have to be absolutely positive that the rest of the room--right down to the shape and size of the room--are going to harmonize with them. Brights include colors like true red, lemon yellow, orange of almost any shade (there is one exception; we'll get to that in a moment), royal purple, and deep blue. Brights should never be used together unless you have a specific look you're going for, usually one of dissonance or discordance, and you really know what you're doing. This is the reason, for example, people say "You should never use red and pink together" or "you should never use blue and purple together." In their true form, these colors are brights, and their natural inclination is to clash.

That isn't to say, for example, that there isn't a case where a bright could be used, or should be used, to paint a wall. Think of a modernistic living room, with walls drenched in red and sleek, stark black furniture. It might not be your style, but colorwise, it works. Rarely, however, will this be the case in your room. In general, if you're in doubt: leave it out. Don't go with brights unless you know what you're going for and how to achieve it.

There is a subcategory of brights that it may be as well to mention: this is the category that includes colors like turquoise, aquamarine, clear blue, cerulean, etc. These colors are still clear and bright, but they have less of a tendency to clash, with each other and with other colors. These can sometimes be referred to as 'soft brights', and while even an amateur colorist can use them without worrying too much, they shouldn't be overdone. A bathroom is a good place for these colors, because, for one thing, colors like turquoise and aquamarine are cool and refreshing, like water. Second, bathrooms are generally small rooms, and the soft brights open them up without feeling overwhelming.

Our third palette is pastels. These are the decorator's friend; they include baby blue, soft or butter yellow, lavendar, etc. Pastels, unlike neutrals, have the benefit of being able to add color and interest to a room that might otherwise lack it. Like neutrals, however, they're a safe palette, with little chance of clashing or irritating. Each color lends a nuance of its own to the room. Blues are calming; greens stimulate life and health; yellow invigorates the intellect.

The fourth and last group is the earth tones. This includes dark chocolate brown, forest green, and pumpkin, that rich, dark orange--the only orange that isn't considered one of the brights. Earth tones, which often seem to overlap with neutrals, are sufficiently rich that they lend an ambience to your room. But, and this is a problem, earth tones tend to be dark. If your room is small, or feels small, these colors will practially stifle you. Earth tones should be used on the walls only in large, airy rooms, where the darker colors ground the room and add a sense of dimension.

Selecting an individual color is largely a question of personal taste. But selecting a color group is a matter of style and cohesion, and there are some basic rules to govern which group you pick your colors from. Neutrals work best with rooms where some other feature--the fabric, perhaps, or a collection of statues or plates or paintings--needs to be brought to the forefront. Pastels work best to add interest to a room that would otherwise be a little bland. Earth tones are good choices for large rooms with lots of light; brights should only be used in carefully designed decorating schemes, and only when you really know what you're doing. Lighter colors make a small room feel larger; darker ones ground a large room and make it feel smaller.

You don't need a degree to work with color. All you need is a strong grasp of the basics and a willingness to be open and experiment.