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