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