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