Roll out a piece of modelling clay about 1cm thick. Press leaves, twigs and flowers into the clay. Remove the plant material to leave an indentation. Place an empty wood frame on top of the clay, pressing it into the edges. Cut the clay from the edges to neaten them. Mix plaster of Paris according to instructions and pour a thin layer into the frame. Press a wire hook into the plaster if you wish to hang the tile. Let set for 30 minutes. Turn over frame and remove the clay cast. Allow plaster to dry overnight. You’re done!