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