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