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