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