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