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