In one sentence, describe what the following article is about:

When arranging your accessories, follow the design principle of using an odd number of decorations. While 3 is the universal number of accessories to use, you can also try arranging 5, 7, or 9 accessories together as well. This looks great and helps add cohesion to your rooms.  For example, when you are placing decorative items on your end tables, put 1 plant, 1 coaster, and 1 candle. If you have an area of your room that looks empty, decorate it with 3 pieces of furniture. You can place a desk, floor lamp, and chair there. It is best to keep a distance of 15 in (38 cm) or more between your coffee table and sofa. That way, you can easily walk around the perimeter. It also helps keep your living room looking open and airy. If your living room is not large enough to accommodate this, try to leave around 1 ft (0.30 m) of space. Your artwork should be at eye level, so you and your guests can easily view them. If your paintings are too low, your ceilings may look limiting and it may look strange on your wall. Generally, your art should be between 56–60 in (140–150 cm) from the floor.  If you are hanging multiple pieces of art, try to keep the center of your entire arrangement at eye level. Some can go below or above if needed. For a more dramatic look, create a gallery wall with art from floor to ceiling. Just make sure no furniture or other items block the artwork. The distance between your sofa and your television depends on the size of your TV. Measure the size of your TV using a ruler or measuring tape, and multiply your measurement by 2. Then, place your couch this distance away from your TV. For example, If your TV is 22 in (56 cm), you should place your couch 44 in (110 cm) away. To add a finishing touch to your room, you can place similar objects or colors together in 1 spot, like on your table or on a shelf. This adds a bit of unity to your accessories while giving your room an artistic touch. For example, if you play music, organize all of your instruments on the mantel in your basement. Place large items like cymbals in the back and put statement items like violins towards the front. Aside from grouping together related objects, you want to limit the number of accessories you have in 1 particular spot so it does not look cramped. Be mindful of negative space, and leave about 1–4 in (2.5–10.2 cm) between your items.  If your coffee table is open, place a stack of a few books, a coaster, and a candle on top. You don't have to load up your accessories on your table just because you have the space. When it comes to decorating, less is more. Choose a few select items that make a statement and avoid distracting from them.

Summary:
Use odd numbers of accessories. Set your coffee table at least 15 in (38 cm) from your sofa. Hang your art so it is center at eye level. Multiply the size of your TV by 2, to determine your viewing distance. Group related objects together to create artful displays. Avoid picking so many accessories that it clutters up your space.