Start by reading the "Stickies" at the top is the forum threads. They are called "Stickies" because they are are always "Stuck" to the top of the list and never get lost. There you can try to understand the basics of room treatment. Please come back with more specific questions and give us a better idea of the space you're working with, a drawing will help. Searching the threads for rooms like yours and questions you have are also good ways to get information here.
One basic observation is that your setup appears to be asymmetrical. For good stereo imaging, symmetry is what you want.
I would suggest, you flick through the whole forum and look for any title or post that can help you with understanding better how to treat a room. I don't know what level you are at, but we are presuming your a beginner which is no problem the forum will guide you.
Don't worry about any technical explanations that many of us have delved into that is secondary, you firstly need to understand the basics of treatment and its all there. Remember most concepts are nothing complicated and need to be conquered for you to move onto the technical aspects of room treatment(if this is really ever important for the laymen). If your worried of not getting it right then ask on, but i will tell you that the information is all in the forum.
Lastly we really can't see what treatment you have in your studio for us to give some advice. I will say that Rock is spot on, symmetry is paramount plus the room is small although for nearfield listening you might get away with it. Stick to the basics I am sure you can manage it in that room. the more the better, at least 10cm thick all reflection points and fill the back wall with as much absorption you can.