How do I decorate these walls?

I would go to Kirlands, or Home Goods and look at large scale paintings. I love the European paintings and have one hanging on a wall that is attached to a cathedral ceiling. So the picture is huge, but did not cost a fortune. It has many beautiful colors and I then got a throw, and some pillows, and Candles etc. You have a good start with the reds/wine colors go from there. Kirklands also has a lot of metal wall hangings. Have fun shopping.

Are you able to paint your walls? I think part of your issue is that everything is the same tone: sofa, rug, walls. Changing the color of your walls would completely change the feel of the room. A beautiful pale aqua would be gorgeous with your sofa and rug. If you can't paint, choose a large round mirror (hunt thrift stores for a bargain and paint the frame if you need to). The round shape would break up all the rectangular lines you have going on. You could hang candle sconces (try to find ones that will hold chunky candles rather than slim ones) on either side of the mirror to put colorful accent candles on. On the other wall find a large print (you can put a large poster in a frame for an economical large piece) that has the colors you love. Then choose pillows or find fabric and make pillows. Go with larger pillows than you have now and do just 3--two that are the same and a third coordinating one in the middle. Or do 2 matching on each end and a third and fourth (one large one small) in the middle. I would also replace the matching ottoman (if possible) with a coffee table or chest (again look at thrift stores) and paint it one of your accent colors. Hope this gives you some ideas for a room that you will love.