How can I effectively join two pieces of wood together using wood glue without the use of clamps?

To effectively join two pieces of wood together using wood glue without clamps, you can use a technique called "rub jointing." Apply a generous amount of wood glue to both surfaces, then rub them together firmly and evenly. Hold the pieces in place for a few minutes until the glue starts to set. This method can create a strong bond without the need for clamps, but it may not be as secure as using clamps.