This is not to say that all items need to be made in the same period, have the same texture or be of the same color, but instead that you should stick with a few themes and make sure that one or two are reflected in each and every piece of furniture that you have in your living room.
Decorative accessories are another important piece in pulling your contemporary look together. Concentrate on getting wall art and pillows that match your contemporary design style. For accent pieces you want the lines to be clean and avoid a lot of clutter. Be certain to add in loads of plain bowls with fruit as well as simple linear floral arrangements and you might even try some black and white photography to get a professional look for your living room. Additional touches such as vintage art deco accessories can help setup your room with a polished decorative appeal, but don't go overboard because with the contemporary look less is better.
An important decorating area that you must work on when decorating your room are your walls. You can make even the plainest walls look nice by incorporating great wall art and decorative accessories. Try adding simple, plain artwork, tribal masks or abstract art to your living room walls to highlight the modern feel of your contemporary theme.