For both rooms to be a pleasure to be in, you need to be careful with where and how you organize your furniture, especially those that can be used in both rooms.  You can get a sofa through which you can divide the living room and the dining room. 

Take note of things that  matter, especially the color themes, materials that you are using, and check if the light is of  the same brightness in both areas so that you are going to maintain a uniform look in both the rooms.

Tips for Separating Your Living Room and Dining Room Combo

1. Use Furniture as a Divider

This is one of the most important things you might want to do concerning this issue. You can use a big sofa or any table that you have that can be used as a  divider of the rooms.

because you are not going to be putting walls on it. The sofa should be in a way that its back is positioned towards the dining area. This will divide both the areas perfectly.

2. Choose Distinct Color Themes

You need to have colors that are going to somehow match and complement each other. 

If you  are considering what colors to choose for the living area, then I would say gray and blue can be a perfect  combination. for the dining space, I would suggest you go for the neutrals, like beige and light brown. The difference in colors acts as a separator on its own. 

Creative Ways to Divide a Living Room and Dining Area Seamlessly

1. Incorporate Area Rugs: You can use rugs as a way to mark the difference between the living area and the dining area.  So,  you can use one rug under  the dining table to make sure that everyone knows and it is easy to demarcate between the two. It not only adds the character and the brightness of the room, it is also going to be functional for its intended purpose. 
2. Use Lighting to Your Advantage: This is very important for people who know the importance of lighting. You can use different lighting in different areas to give a different definition to each of the rooms without having walls. You can have soft and light lights for the living area because people will be talking and just relaxing over there, while for the dining area,  you might need a chandelier above or any brighter lights. 
3. Consider Ceiling Treatments:  The architecture of your house also matters because it will give a different vibe to each room. So you can use a different color for the ceiling aligned with the dining table and another different color for the area aligned with the living room.
4. Employ Vertical Elements: While choosing furniture or any other pieces in your house, make sure they are vertical. This will allow your space to look wider. This can also be used as a room divider without disturbing the moods of people or without hindering the display. 
5. Play with Wall Treatments: In both areas, the walls are supposed to be decorated in a way that is different from the other.  So, for a tip, you can keep the neutral walls in your living room. On the other hand, you can just give some decorations to your dining area so that you give it more character and texture. 

Maximizing Function in a Living Room-Dining Room Combo

• Optimize Layout for Flow: You have to have a layout that will work for you in the first place.  The dining table, of course, should be close enough to the kitchen so that it’s easy for you to just prepare and serve the food without walking a very long distance. And then in the living area, make sure that there are enough spaces where people can move in between furniture.
• Multi-Functional Furniture: It is wiser if you are going to get or buy furniture that can be used for more than one purpose.  Because this is going to save you space and also going to utilize the amount of storage you have. You are going to use it for more than one reason. And decorate it the way you want it to be.
• Smart Storage Solutions: There are other ways that you can use to make the storage not really much of a bedding. The sideboard that you have in your bedroom can be used to store some of the things that come from the living area. If you have built-in shelves, then that is a good thing because these can be put in both places ..

Effective Layout Strategies for a Living and Dining Room Combination

• Define Areas with Structural Elements: You can use columns or structural elements to demarcate that line between the living and the dining room, so that  the spaces you have will not be compromised but also you are going to feel  where exactly you are without any problems.
• Harmonious Design Elements: It is important to make the rooms share a little bit of decorative pieces in common so that there is some sense of oneness and it feels like the rooms are connected in a way.
• Flexible Seating Arrangements: It is not supposed to be a hassle for you to sit. Choose chairs and tables that are comfortable to sit on and can be moved easily. By doing this, you can allow yourself to make adjustments whenever they are needed.
• Visual Separators: There are things that you can use just for simple separation, and everyone can see it.  It is easy to use things like topless in your room to demarcate that line without putting too much effort. And at the end of the day, they are still going to contribute to the aesthetic of your house.

Conclusion

All these tips will help you to demarcate  your living room and your dining room without any problems and make both the rooms have some sense of continuity.