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