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