To begin with, the open floor layout gives you a huge space to decorate. That's cool and yet it can be extremely challenging to deal with.   Here's what we recommend you do to make the task easier:
  1. Identify the functions of the space- If you are dealing with a large open space, you will need to break it up into parts according to what it is going to be used for. Usually, such spaces are divided into the living room and the dining areas. Obviously, the dining area will be closer to the kitchen. However, when it comes to the living room,  you will need to figure out if you want a TV in there or prefer to have it in the bedroom. However you plan things, try not to overstuff your space. There needs to be enough room for pathways, meaning people should be able to walk around the room comfortably, without banging into things.
  2. Align the furniture according to the functionality of the space- Next, if the living room is going to be your main TV watching area, you will need to identify the spot for the TV. And if you really aren't sure about it, we recommend you opt for a hidden TV lift cabinet. Another relevant question is, will the TV go up on a wall, or do you want to utilize an odd corner for the TV? Does a wall mount work for you or do you prefer a hidden TV lift cabinet? If you mount the TV on the wall, you will be stuck with that particular wall being the focal point of the room. If you want to be able to move the TV around without messing up the walls, a TV lift cabinet is an option to consider. We recommend getting a hidden TV lift cabinet simply because it will let you play around with the space and furniture whenever you want to. You won't be stuck with the same layout for years together.
  3. Tie in the look with a theme- Since the living and dining rooms in an open layout offer an extended space, it becomes necessary to tie in the decor of both areas together. It needs to come together as one space, yet be visually separated. You could use the color scheme as the unifying agent. The same color could feature on cushions in the living room, flowers in the dining room, some artwork, and so on. The aim is to find ways to connect the spaces so that they are not extremely contrasting. The eye needs to be able to glide from one space to another without any abrupt visual changes. Again, the secret lies in how creative you can get with the color scheme and the textures.
You'll need some research, lots of visualization, and a tad bit of inspiration. Once you are open to new ideas, your open layout decor won't be a problem at all!