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