Avoid using heavy furniture such as big stuff sofas, wardrobes or bookshelves that have closed shutters. Instead if you are using sofas with sleek frame (like the one out of bamboo furniture) this will likely create more transparency and will help in perception of more space. If kept open will reveal more wall surface behind them and reduce the "bulky" look, also storage units such as TV unit, book shelves. In the interior space that is certainly empty the perception of "small or big" is normally decided depending upon the dimensions of the space. The volume of the space defined by the boundaries of ceiling, floor and walls defines the space. The openings in the walls further help in reducing the bulkiness of the space.