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