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