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