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)(11,13)(12,20)(14,15)(16,18)(17,23)(19,24)(21,22)(25,26,31,33)(27,32,28,36)(29,30,39,40)(34,38,37,35)(2,5)(6,7)(10,15)(11,18)(17,20)(19,21)(25,27,31,28)(26,32,33,36)(29,37,39,34)(30,35,40,38)(1,2)(3,6)(4,5)(7,8)(10,15)(13,16)(17,20)(22,24)(25,28,31,27)(26,32,33,36)(29,37,39,34)(30,38,40,35)(1,2)(3,6)(4,5)(7,8)(9,11)(10,16)(12,21)(13,15)(14,18)(17,22)(19,23)(20,24)(25,29)(26,30)(27,34)(28,37)(31,39)(32,38)(33,40)(35,36) involution — undirected(1,3,4,8)(2,6,5,7)(9,12,14,23)(10,17,15,20)(11,19,18,21)(13,22,16,24)(25,30)(26,29)(27,35)(28,38)(31,40)(32,37)(33,39)(34,36)(9,13,14,16)(10,11,15,18)(12,22,23,24)(17,19,20,21)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.