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Really all you are doing is trying to break up reflections so it depends on your room. Hanging some heavy drapes will do the job and anything like sofas, bookcases etc can help to break up a blank, hard surface wall that creates a lot of echo. Cheap trick – clap your hands and see if you get an echo. If you do that will definitely come out on recordings and muddy them up so anything you can put on the walls to absorb the sound will help.
If you have a studio set up like I do I also look at the direction my monitor speakers are pointing and put panels to catch the first reflections that bounce off the side walls and I also have panels on the back walls. But this gets a bit more technical than you’d need for just stopping a room being too ‘lively’ for recording.