Well, imagine the two of us trying to decide on rugs. The room is getting to where I like it and we decide that we need a rug for some color and pattern to our living room. After searching I decide it is ok to put a flat woven rug on top of carpet (I wish we had hardwood everywhere, but that is a story for another day). Neither of us can find something we like, in the right size. There are rules to the sizes I tell him. Bigger is better. The colors don’t go as well with my paint and chairs. I am frustrated because there are way more paint colors to choose from than there are rugs.
So, my advice to you is: start with the rug. Find one that you like, research the styles of rooms that you are leaning towards. Shop for rugs first, before you decide on paint color. Its easier to have the rug and be able to pull a paint color from there, rather than trying to find a rug that meets all of your needs and then trying to get it to match your paint color. The area rug will be something you want your friends to see, the focal point. The paint color is what creates the mood of the room. It is important, but not the focal point.
What are the rug rules you ask? I have found some easy diagrams to share with you. First, the rug needs to be large enough for all of the chairs to be on top of the rug. If it is to be placed under the dining table the size should accommodate a chair to be pulled out from the table without being taken off the rug.