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