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