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