1. Illusion is a trick that works well. Put up a mirror that makes the garden look twice it's size. 2. A group of grasses creates the illusion of a meadow. It also creates movement and shadows. 3. Strong lines of paths add interest. 4. A focal point is necessary to make one stop and look. A pot or a statue would do it. 5. A low retaining wall of 30 cm gives one the idea of a bigger space.