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