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