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