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