When you next get bored with your home then you could try randomly rearranging the furniture, until you find a layout that appeals. But if that sounds too much like hard work, then we may have a better idea. Sweet Home 3D is a free, open-source interior design tool that helps you plan out everything from a revamped room to entire new house, and includes a 3D preview of how your design will look, so you can get everything just right before you start work.
If you've tried similar tools before then you'll know that they can be very tricky to use, but Sweet Home 3D is different. Everything you need to "dress" a room is immediately available in a tree view: chairs, stools, bookcases, desks, sinks, beds, baths and more. All you have to do is choose what you need, drag and drop it onto the room area, and position the object to suit your needs.
As you work, the program can display and update an "aerial view" of your room, which alone gives you a very good idea of the layout. But if you want the true 3D effect, just click 3D View > Virtual Visit, then use the mouse to move around the room and see how it looks from different angles.
If Sweet Home 3D doesn't contain all the objects you need, then it's easy to add more. The Furniture Import Wizard can import 3D objects in OBJ, LWS, or 3DS formats, and there are plenty of compatible free models available online.
And if you want to share your plan with someone else, then the program can print it directly to a PDF document. Or you're able to export it as an SVG file, which may let them customise the design with their own ideas.
Sweet Home 3D 4 is a major update. See the history for more information.