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