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