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