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