I guess if you want to try to hear the ideal condition of your room and seating position you can try to place your speakers in near field position. Essentially you are keeping your speakers away from the walls and moving it closer to the center of the room. It's a ridiculous layout, but it gives you a quick, easy idea of an ideal case and whether it's worth doing anything compared to before.
On the other hand an easy way is to test acoustics is to put pillows on that living room table that is usually between your speakers and more pillows against the flat wall that is usually above the couch that is against the wall. You can also put pillows or towels on the 1st flat surface closest to the sides of your speakers.
You can then buy and put those porous color in the cloth paintings with a open cell foam behind the canvas in those areas.