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