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