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