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