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