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