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