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