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