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