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