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