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