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)(11,15,18,13)(12,16,20,24)(19,23,21,22)(25,26,31,35)(27,30,29,33)(28,34,39,32)(36,38,37,40)(2,5)(6,7)(9,11)(10,15)(12,19)(13,17)(14,18)(16,23)(20,21)(22,24)(25,27,31,29)(26,30,35,33)(28,37,39,36)(32,38,34,40)(1,2)(3,6)(4,5)(7,8)(11,18)(12,20)(13,15)(16,24)(25,28,31,39)(26,32,35,34)(27,36,29,37)(30,40,33,38)(1,3)(2,6)(4,8)(5,7)(9,11)(10,15)(12,21)(13,17)(14,18)(16,22)(19,20)(23,24)(25,29,31,27)(26,33,35,30)(28,36,39,37)(32,40,34,38)(9,12)(10,16)(11,19)(13,22)(14,20)(15,23)(17,24)(18,21)(25,28)(26,34)(27,36)(29,37)(30,38)(31,39)(32,35)(33,40) involution — undirected(9,13,14,15)(10,11,17,18)(12,22,20,23)(16,19,24,21)(25,30,31,33)(26,27,35,29)(28,38,39,40)(32,37,34,36)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.