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