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