One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6)(7,8)(9,10,14,11)(12,15,19,17)(13,18,21,16)(20,23,24,22)(25,26,31,33)(27,32,36,39)(28,38,35,30)(29,34,40,37)(2,6)(3,7)(12,19)(15,17)(20,24)(22,23)(25,27)(26,32)(28,29)(30,37)(31,36)(33,39)(34,38)(35,40) involution — undirected(1,3,5,7)(2,4,6,8)(10,11)(15,17)(16,18)(22,23)(26,33)(27,36)(28,35)(34,37)(1,4)(2,7)(3,6)(5,8)(9,11,14,10)(12,17,19,15)(13,18,21,16)(20,23,24,22)(25,28,31,35)(26,30,33,38)(27,29,36,40)(32,37,39,34)(9,12,14,19)(10,15,11,17)(13,20,21,24)(16,22,18,23)(25,29)(26,34)(27,35)(28,36)(30,32)(31,40)(33,37)(38,39)(9,13,14,21)(10,16,11,18)(12,20,19,24)(15,22,17,23)(25,30)(26,35)(27,37)(28,33)(29,39)(31,38)(32,40)(34,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.