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