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