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