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