To decorate your living room for Christmas, start by adding some festive elements to the room. Place a Christmas tree in a prominent position, and decorate it with lights, ornaments, and garlands. You can also add some other decorations like stockings, wreaths, or other Christmas-themed items. To make the space more cozy, add some blankets or pillows in Christmas colors and patterns. You can also add some scented candles or potpourri to give the room a festive and pleasant smell. Don't forget to add some festive music or movies to create an atmosphere of joy and celebration.