Various elements have to be considered in interior design. One of the most important will be the room itself. That's why it's fundamental to understand how you can use and customize the different components in a room to create a pleasant environment. Each component has to be considered in your design nevertheless keep in mind that the most important thing will be the "whole effect".
The first element to consider is the wall. It's the widest area you will be able to customize. As a wall is a material itself, sometimes you don't need to cover it up. For example, a stone wall can be kept natural as it will add character to the room and will create focal point. However, if you want to add style and texture to the room, you will have to use some wall-surfacing materials. Wood panelling and plywoods will create a warm atmosphere and are very good solutions for important spaces. More traditional but highly decorative, wallpapers stay one of the most used materials in interior design. Eventually, you can also paint the walls, which is one of the best and least expensive interior decorating techniques... it will add texture and depth to your room.
The second element that will be part of the interior design is the floor. As the walls, the floor can be kept natural (concrete, brick...) but most of the time you will have to use floor covering materials. Synthetic floor coverings also known as resilient floors are great flooring material as they are cheap and easy to maintain. Nevertheless, this type of floor is made to imitate other materials (stone, mosaic...) and the result is often not as good as the real materials. Suitable for almost any space and very easy to maintain, quarry tiles can also be an excellent option though installation requires pouring cement over the existing floor (which can be sometimes a problem in existing buildings). At last, another alternative can be chosen to customize a floor: the wood. Although it requires more care, this very popular flooring material will add warmth and stylishness to the room.
Finally, the last element to consider is the ceiling. Although it's often ignored in interior design, the ceiling can play a very important part in the "whole effect". Two or three centuries ago, decorated ceilings with ornaments were part of beautiful interiors. By adding textural effects with paint or wood, the room design can be totally changed.
Interior design is made of multiple concepts and elements (window, door, furniture, light...). However, walls, floor and ceiling are the foundation of your design that's why it's so important to think about these few elements first and define with great care how to customize them.