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)(11,15)(12,25)(13,17)(14,19)(16,28)(18,20)(21,29)(22,36)(23,31)(24,32)(26,34)(27,33)(30,35)(37,39)(38,40) involution — undirected(2,5)(6,8)(9,11,20,21,14,24,13,23)(10,15,18,29,19,32,17,31)(12,22,28,35,26,37,27,38)(16,30,34,39,33,40,25,36)(1,3)(2,6)(4,7)(5,8)(11,21)(13,20)(15,29)(17,18)(22,35)(23,24)(25,34)(27,28)(30,39)(31,32)(36,40)(37,38) involution — undirected(3,7)(6,8)(9,12)(10,16)(11,22)(13,27)(14,26)(15,30)(17,25)(18,34)(19,33)(20,28)(21,35)(23,38)(24,37)(29,39)(31,36)(32,40) 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.