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