One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,5)(3,7,8,6)(12,20)(16,21)(19,24)(22,23)(25,26,31,35)(27,36,40,32)(28,29,39,33)(30,34,37,38)(2,5)(6,7)(9,10)(11,15)(12,21)(13,17)(14,18)(16,20)(19,22)(23,24)(25,27)(26,32)(28,37)(29,34)(30,39)(31,40)(33,38)(35,36) involution — undirected(1,2)(3,6)(4,5)(7,8)(9,11)(10,13)(12,19)(14,17)(15,18)(16,22)(20,24)(21,23)(25,26,31,35)(27,32,40,36)(28,33,39,29)(30,34,37,38)(1,2)(3,6)(4,5)(7,8)(9,11)(10,15)(12,19)(13,18)(14,17)(16,23)(20,24)(21,22)(25,28)(26,33)(27,37)(29,35)(30,40)(31,39)(32,38)(34,36) involution — undirected(1,3,4,8)(2,6,5,7)(9,12)(10,16)(11,19)(13,22)(14,20)(15,23)(17,24)(18,21)(25,29,31,33)(26,28,35,39)(27,38,40,34)(30,36,37,32)(9,13,14,15)(10,17,18,11)(12,22,20,23)(16,24,21,19)(25,30,31,37)(26,34,35,38)(27,39,40,28)(29,36,33,32)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.