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