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