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