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