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