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