Lattice usually consists of pieces of wood that crisscross each other. When the sun shines through lattice, it can create some unique shadows. I didn't have access to any lattice so I used the shadows created by the blinds in my dining room window. The horizontal lines crossed by the strings running vertically through them created a lattice type pattern. When the sun came in, it cast a distinct pattern across my books and cup of tea.
If you don't have access to lattice, look for something that has lines or holes that create shadows when light is shined through them. If you don't have sunshine to create the shadows how about using a lamp or flashlight as your light source. What patterns will your lattice create?
