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