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