Put them in stacks or rows, make long lines or messy collages, stuff them in a bag or a box or an old coffee cup or lay them out on the floor. Lots of collections would occur naturally also- such as cars in a parking lot, a crate of apples, a basket of oranges, a bowl of cherrries, a container of hair clips .. you get the idea.... The photo MUST contain at least two items which are either the same or similar enough to be in the same "collection".