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