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