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