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